<SEC-DOCUMENT>0001193125-20-138782.txt : 20200511
<SEC-HEADER>0001193125-20-138782.hdr.sgml : 20200511
<ACCEPTANCE-DATETIME>20200511141058
ACCESSION NUMBER:		0001193125-20-138782
CONFORMED SUBMISSION TYPE:	S-8
PUBLIC DOCUMENT COUNT:		5
FILED AS OF DATE:		20200511
DATE AS OF CHANGE:		20200511
EFFECTIVENESS DATE:		20200511

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PACKAGING CORP OF AMERICA
		CENTRAL INDEX KEY:			0000075677
		STANDARD INDUSTRIAL CLASSIFICATION:	PAPERBOARD CONTAINERS & BOXES [2650]
		IRS NUMBER:				364277050
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-8
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-238155
		FILM NUMBER:		20864041

	BUSINESS ADDRESS:	
		STREET 1:		1955 W FIELD CT
		CITY:			LAKE FOREST
		STATE:			IL
		ZIP:			60045
		BUSINESS PHONE:		8474823000

	MAIL ADDRESS:	
		STREET 1:		1955 W FIELD CT
		CITY:			LAKE FOREST
		STATE:			IL
		ZIP:			60045
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-8
<SEQUENCE>1
<FILENAME>d928020ds8.htm
<DESCRIPTION>S-8
<TEXT>
<HTML><HEAD>
<TITLE>S-8</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the Securities and Exchange Commission on May&nbsp;11, 2020 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></P>
<P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM <FONT
STYLE="white-space:nowrap">S-8</FONT> </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>PACKAGING CORPORATION OF AMERICA </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact name of registrant as specified in its charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:8pt" ALIGN="center">


<TR>

<TD WIDTH="50%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="48%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B><FONT STYLE="white-space:nowrap">36-4277050</FONT></B></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or other jurisdiction of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>incorporation or organization)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"><B>1 North Field Court, Lake Forest, Illinois</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>60045</B></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="top" ALIGN="center"><B>(Address of Principal Executive Offices)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>(Zip Code)</B></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Packaging Corporation of America Retirement Savings Plan for Salaried Employees </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Packaging Corporation of America Thrift Plan for Hourly Employees </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full title of the plan) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Kent A. Pflederer </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Senior Vice President, General Counsel and Secretary </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Packaging Corporation of America </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>1 North Field Court </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Lake
Forest, Illinois 60045 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(847) <FONT STYLE="white-space:nowrap">482-3000</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name, address, including zip code, and telephone number, including area code, of agent for service) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Copies to: </B></P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>James S.
Rowe </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Elisabeth M. Martin </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Kirkland&nbsp;&amp; Ellis LLP </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>300 North LaSalle </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Chicago, Illinois 60654 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(312) <FONT STYLE="white-space:nowrap">862-2000</FONT> </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Indicate by check mark whether
the registrant is a large accelerated filer, an accelerated filer, a <FONT STYLE="white-space:nowrap">non-accelerated</FONT> filer, a smaller reporting company or an emerging growth company. See the definitions of &#147;large accelerated
filer,&#148; &#147;accelerated filer,&#148; &#147;smaller reporting company&#148; and &#147;emerging growth company&#148; in Rule <FONT STYLE="white-space:nowrap">12b-2</FONT> of the Exchange Act. </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="17%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="57%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="21%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="2%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9746;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">Non-accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Emerging&nbsp;growth&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section&nbsp;7(a)(2)(B) of the Securities Act.&nbsp;&nbsp;&#9744; </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CALCULATION
OF REGISTRATION FEE </B></P> <P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:8pt" ALIGN="center">


<TR>

<TD WIDTH="41%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="16%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD></TR>


<TR STYLE="font-size:1px; ">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title of securities</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>to be registered</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Amount</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>to be</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>registered
(1)</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Proposed</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>maximum</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>offering&nbsp;price</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>per&nbsp;share&nbsp;(2)</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Proposed</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>maximum</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>aggregate</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>offering&nbsp;price&nbsp;(2)</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Amount of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Registration&nbsp;Fee(3)</B></P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Common Stock, $0.01 par value per share</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">&nbsp;&nbsp;&nbsp;979,802&nbsp;shares&nbsp;(4)</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$94.745</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$&nbsp;&nbsp;92,831,340.49</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$12,049.51</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Common Stock, $0.01 par value per share</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">&nbsp;&nbsp;&nbsp;503,912&nbsp;shares&nbsp;(5)</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$94.745</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$&nbsp;&nbsp;47,743,142.44</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$&nbsp;&nbsp;6,197.06</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Total</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">1,483,714&nbsp;shares&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$94.745</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$140,574,482.93</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$18,246.57</TD></TR>
<TR STYLE="font-size:1px; ">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="font-size:1px; ">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
</TABLE> <P STYLE="font-size:3pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:8.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000;width:11%">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Pursuant to Rule 416 under the Securities Act of 1933, as amended (the &#147;Securities Act&#148;), this
Registration Statement shall be deemed to cover any additional shares of Common Stock which may be issuable under the plans to reflect stock splits, stock dividends, mergers and other capital changes. In addition, pursuant to Rule 416(c) under the
Securities Act, this Registration Statement also covers an indeterminate amount of interests in the Packaging Corporation of America Retirement Savings Plan for Salaried Employees and the Packaging Corporation of America Thrift Plan for Hourly
Employees to be offered or sold pursuant to the terms described therein. </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Estimated pursuant to Rules 457(c) and (h)&nbsp;under the Securities Act solely for purposes of calculating the
amount of the registration fee based upon the average of the high and low prices reported for the shares on the New York Stock Exchange on May 7, 2020. </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Pursuant to Rule 457(p) under the Securities Act, a portion of the registration fee is offset by registration
fees of $1,372 previously paid by the registrant with respect to 283,714 unissued shares of Common Stock registered under a Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (File
<FONT STYLE="white-space:nowrap">No.&nbsp;333-206801)</FONT> filed by Packaging Corporation of America on September&nbsp;8, 2015 (the &#147;Prior Registration Statement&#148;). A post-effective amendment to the Prior Registration Statement to
deregister such 283,714 unissued shares is being filed filed contemporaneously with the filing of this Registration Statement.</P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(4)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Represents shares of Common Stock to be acquired under the Packaging Corporation of America Retirement Savings
Plan for Salaried Employees. </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(5)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Represents shares of Common Stock to be acquired under the Packaging Corporation of America Thrift Plan for
Hourly Employees. </P></TD></TR></TABLE> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXPLANATORY NOTE </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We are filing this Registration Statement to register (i)&nbsp;an additional 979,802 shares of our common stock, par value $0.01 per share
(the &#147;Common Stock&#148;), that may be acquired by Company employees under the Packaging Corporation of America Retirement Savings Plan for Salaried Employees (the &#147;Savings Plan&#148;) and the associated plan interests and (ii)&nbsp;an
additional 503,912 shares of our Common Stock that may be acquired by Company employees under the Packaging Corporation of America Thrift Plan for Hourly Employees (the &#147;Thrift Plan&#148; and together with the Savings Plan, the
&#147;Plans&#148;) and the associated plan interests. The full text of the Thrift Plan and the Savings Plan is available on the Securities and Exchange Commission&#146;s (the &#147;Commission&#148;) website as an exhibit to our Registration
Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg. <FONT STYLE="white-space:nowrap">No.&nbsp;333-33176),</FONT> filed with the Commission on March&nbsp;23, 2000 (the &#147;Original Registration Statement&#148;). </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Effective January&nbsp;1, 2017, the Boise Paper Holdings, L.L.C. Savings Plan (the &#147;Boise Savings Plan&#148;) was merged with and into
the Savings Plan, and effective January&nbsp;1, 2020, the Boise Paper Holdings, L.L.C. Retirement Savings Plan (the &#147;Boise Retirement Savings Plan&#148;) was merged with and into the Thrift Plan. The shares of Common Stock being registered for
offer and sale pursuant to the Savings Plan include 179,802 shares of Common Stock previously registered for issuance under Form <FONT STYLE="white-space:nowrap">S-8</FONT> Registration Statement (File
<FONT STYLE="white-space:nowrap">No.&nbsp;333-206801),</FONT> as filed with the Commission on September&nbsp;8, 2015 (the &#147;Prior Registration Statement&#148;), for offer and sale pursuant to the Boise Savings Plan, which remained unissued and
available immediately prior to the merger, and 800,000 shares that had not previously been registered. The shares of Common Stock being registered for offer and sale pursuant to the Thrift Plan include 103,912 shares of Common Stock previously
registered for issuance under the Prior Registration Statement, for offer and sale pursuant to the Boise Retirement Savings Plan, which remained unissued and available immediately prior to the merger, and 400,000 shares that had not previously been
registered. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We previously filed the Original Registration Statement on March&nbsp;23, 2000 covering, among other things, 5,800,000 shares
of our Common Stock under the Savings Plan and the Thrift Plan. On May&nbsp;29, 2009, we filed an additional Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg.
<FONT STYLE="white-space:nowrap">No.&nbsp;333-159576)</FONT> to register, among other things, (i)&nbsp;an additional 600,000 shares of our Common Stock that may be acquired by Company employees under the Thrift Plan and (ii)&nbsp;an additional
1,400,000 shares of our Common Stock that may be acquired by Company employees under the Savings Plan. On February&nbsp;22, 2012, we filed an additional Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg. <FONT
STYLE="white-space:nowrap">No.&nbsp;333-179620)</FONT> to register: (i)&nbsp;an additional 800,000 shares of our Common Stock that may be acquired by Company employees under the Savings Plan; and (ii)&nbsp;an additional 1,200,000 shares of our
Common Stock that may be acquired by Company employees under the Thrift Plan. On March&nbsp;13, 2015, we filed an additional Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg.
<FONT STYLE="white-space:nowrap">No.&nbsp;333-202723)</FONT> to register: (i)&nbsp;an additional 1,200,000 shares of our Common Stock that may be acquired by Company employees under the Savings Plan; and (ii)&nbsp;an additional 300,000 shares of our
Common Stock that may be acquired by Company employees under the Thrift Plan. Pursuant to General Instruction E to Form <FONT STYLE="white-space:nowrap">S-8,</FONT> the contents of the Original Registration Statement, including the periodic and
current reports that we filed with the Commission after the effectiveness of the Original Registration Statement, are incorporated herein by reference except to the extent supplemented, amended or superseded by the information set forth herein. Any
items in the Original Registration Statement not expressly changed hereby shall be as set forth in the Original Registration Statement. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">1 </P>

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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;3. Incorporation of Documents by Reference. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The following documents filed by Packaging Corporation of America (the &#147;Company&#148;) with the Commission are incorporated in this
Registration Statement by reference: </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">(a) the Company&#146;s Annual Report on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/75677/000156459020006774/pkg-10k_20191231.htm">Form
 <FONT STYLE="white-space:nowrap">10-K</FONT></A> for the fiscal year ended December&nbsp;31, 2019, filed on February&nbsp;26, 2020; </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">(b)
the Company&#146;s Quarterly Report on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/75677/000156459020021593/pkg-10q_20200331.htm">Form <FONT STYLE="white-space:nowrap">10-Q</FONT></A> for the quarter ended
March&nbsp;31, 2020, filed on May&nbsp;6, 2020; </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">(c) the Company&#146;s Current Report on Form <FONT STYLE="white-space:nowrap">8-K</FONT>
filed on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/75677/000119312520056276/d884126d8k.htm">February&nbsp;28, 2020</A>, the Company&#146;s Current Report on Form
<FONT STYLE="white-space:nowrap">8-K/A</FONT> filed on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/75677/000119312520056359/d885978d8ka.htm">February&nbsp;28, 2020</A>, the Company&#146;s Current Report on
Form <FONT STYLE="white-space:nowrap">8-K</FONT> filed on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/75677/000156459020018916/pkg-8k_20200427.htm">April&nbsp;28, 2020</A>, other than the portions furnished
under Items 2.02 and 9.01 thereof, and the Company&#146;s Current Report on Form <FONT STYLE="white-space:nowrap">8-K</FONT> filed on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/75677/000119312520134376/d890367d8k.htm">May&nbsp;6,
 2020</A>; </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">(d) the Savings Plan&#146;s Annual Report on <A HREF="http://www.sec.gov/Archives/edgar/data/75677/000119312519186024/d764908d11k.htm">Form
 <FONT STYLE="white-space:nowrap">11-K</FONT></A> for the fiscal year ended December&nbsp;31, 2018; </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">(e) the Thrift Plan&#146;s Annual
Report on <A HREF="http://www.sec.gov/Archives/edgar/data/75677/000119312519186018/d756801d11k.htm">Form <FONT STYLE="white-space:nowrap">11-K</FONT></A> for the fiscal year ended December&nbsp;31, 2018; and </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">(f) the description of the Company&#146;s common stock, par value $0.01 per share, included under the caption &#147;Description of Capital
Stock&#148; in the Prospectus forming a part of the Company&#146;s Registration Statement on <A HREF="http://www.sec.gov/Archives/edgar/data/75677/000104746999035457/0001047469-99-035457.txt">Form <FONT STYLE="white-space:nowrap">S-1</FONT></A>,
initially filed with the Commission on September&nbsp;13, 1999 (Registration <FONT STYLE="white-space:nowrap">No.&nbsp;
333-86963),</FONT> which description has been incorporated by reference in Item 1 of the Company&#146;s Registration Statement on <A HREF="http://www.sec.gov/Archives/edgar/data/75677/000104746999038973/0001047469-99-038973.txt">Form <FONT
STYLE="white-space:nowrap">8-A</FONT></A>, filed pursuant to Section&nbsp;12 of the Securities Exchange Act of 1934, as amended (the &#147;Exchange Act&#148;), on October&nbsp;15, 1999 (Registration
<FONT STYLE="white-space:nowrap">No.&nbsp;001-15399),</FONT> including any amendments or reports filed for the purpose of updating such description. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">All documents subsequently filed by the Company and the Plans pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act subsequent
to the date of this Registration Statement (other than any documents or portions thereof that are furnished under Item 2.02 or Item 7.01 of Form <FONT STYLE="white-space:nowrap">8-K,</FONT> including any exhibits included with such Items), prior to
the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part hereof from
the date of filing of such documents. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Any statement contained in a document incorporated or deemed to be incorporated by reference herein
shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein
modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;5. Interests of Named Experts and Counsel. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Certain legal matters in connection with the issuance of the shares of Common Stock offered hereby will be passed upon for the Company by Kent
A. Pflederer, Senior Vice President, General Counsel and Secretary of the Company. Mr.&nbsp;Pflederer is the direct beneficial owner of 51,113 shares of the Company&#146;s Common Stock and the indirect beneficial owner of 3,693 shares of the
Company&#146;s Common Stock through the Savings Plan. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;8. Exhibits. </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD></TD>

<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman"><B>Exhibit</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>Description</B></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/75677/000091205700013220/0000912057-00-013220.txt">Packaging Corporation of America Thrift Plan for Hourly Employees and First Amendment of Packaging Corporation of America Thrift Plan for
Hourly Employees (incorporated herein by reference to the Company&#146;s Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> File <FONT STYLE="white-space:nowrap">No.&nbsp;333-33176),</FONT> filed on March&nbsp;23, 2000).
</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/75677/000091205700013220/0000912057-00-013220.txt">Packaging Corporation of America Retirement Savings Plan for Salaried Employees (incorporated herein by reference to the Company&#146;s
 Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> File <FONT STYLE="white-space:nowrap">No.&nbsp;333-33176),</FONT> filed on March&nbsp;23, 2000). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928020dex51.htm">Opinion of Kent A. Pflederer, Esq. (filed herewith). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>5.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/75677/000091205700013220/0000912057-00-013220.txt">Undertaking of the Company (incorporated herein by reference to Exhibit 5.2 to the Company&#146;s Registration Statement on Form <FONT
STYLE="white-space:nowrap">S-8</FONT> (Reg. <FONT STYLE="white-space:nowrap">No.&nbsp;333-33176),</FONT> filed on March&nbsp;23, 2000). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928020dex231.htm">Consent of KPMG LLP (filed herewith). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928020dex232.htm">Consent of KPMG LLP (filed herewith) </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928020dex233.htm">Consent of KPMG LLP (filed herewith). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928020dex51.htm">Consent of Kent A. Pflederer, Esq. (included in Exhibit 5.1). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="#sig">Power of Attorney (set forth on the signature page of this Registration Statement). </A></TD></TR>
</TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">2 </P>

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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;9. Undertakings. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(a) The undersigned registrant hereby undertakes: </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(1) to file, during any period in which offers or sales are being made, a post-effective amendment to this Registration
Statement: </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(i) to include any prospectus required by Section&nbsp;10(a)(3) of the Securities Act; </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(ii) to reflect in the prospectus any facts or events arising after the effective date of this Registration Statement (or most
recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this Registration Statement. Notwithstanding the foregoing, any increase or decrease in the volume of
securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with
the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a twenty percent change in the maximum aggregate offering price set forth in the &#147;Calculation of Registration Fee&#148; table in
the effective registration statement; and </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(iii) to include any material information with respect to the plan of
distribution not previously disclosed in this Registration Statement or any material change to such information in this Registration Statement; </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman"><I>provided,</I> <I>however</I>, that paragraphs (a)(1)(i) and (a)(1)(ii) of this section do not apply if the information required to be
included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Company pursuant to section 13 or section 15(d) of the Exchange Act that are incorporated by reference in this
Registration Statement; </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(2) that, for the purpose of determining any liability under the Securities Act, each such
post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; and </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(3) to remove from registration by means of a post-effective amendment any of the securities being registered which remain
unsold at the termination of the offering. </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(b) The undersigned registrant hereby undertakes that, for purposes of determining any
liability under the Securities Act, each filing of the Company&#146;s annual report pursuant to Section&nbsp;13(a) or Section&nbsp;15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan&#146;s annual report
pursuant to Section&nbsp;15(d) of the Exchange Act) that is incorporated by reference in this Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at
that time shall be deemed to be the initial bona fide offering thereof. </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(c) Insofar as indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Commission such indemnification is
against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director,
officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless
in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be
governed by the final adjudication of such issue. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">3 </P>

</DIV></Center>


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<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><A NAME="sig"></A>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form <FONT STYLE="white-space:nowrap">S-8</FONT> and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Lake Forest, State of
Illinois, on May&nbsp;11, 2020. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="12%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="87%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><B>PACKAGING CORPORATION OF AMERICA</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Kent A. Pflederer</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Name:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Kent A. Pflederer</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Title:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Senior Vice President, General Counsel and Secretary</TD></TR>
</TABLE></DIV> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>POWER OF ATTORNEY </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Mark W. Kowlzan, Kent A. Pflederer
and Robert P. Mundy, and each or any of them, his or her true and lawful <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and agent, with full power of substitution and resubstitution, for him or her
in his or her name, place and stead, in any and all capacities, to sign any and all amendments to this Registration Statement (including post-effective amendments), and any and all additional registration statements pursuant to Instruction E to Form
<FONT STYLE="white-space:nowrap">S-8</FONT> and any and all documents in connection therewith, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto
said <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and agent full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises in
order to effectuate the same, as fully to all intents and purposes as he or she might or could do in person, and hereby ratifies, approves and confirms all that his or her said
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, each acting alone, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the
capacities indicated on May&nbsp;11, 2020. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="47%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="4%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman">Signature</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Title</P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Mark Kowlzan</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Mark Kowlzan</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chief Executive Officer and Chairman of the Board</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(Principal Executive Officer)</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Robert P. Mundy</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Robert P. Mundy</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Executive Vice President and Chief Financial Officer</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(Principal Financial Officer)</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Pamela A. Barnes</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Pamela A. Barnes</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Senior Vice President, Finance and Controller</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(Principal Accounting Officer)</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Cheryl K. Beebe</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Cheryl K. Beebe</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
</TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always">
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<Center><DIV STYLE="width:8.5in" align="left">

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


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<TD WIDTH="4%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Duane C. Farrington</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Duane C. Farrington</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Donna A. Harman</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Donna A. Harman</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Robert C. Lyons</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Robert C. Lyons</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Thomas P. Maurer</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Thomas P. Maurer</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Samuel M. Mencoff</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Samuel M. Mencoff</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Roger B. Porter</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Roger B. Porter</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Thomas S. Souleles</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Thomas S. Souleles</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Paul T. Stecko</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Paul T. Stecko</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ James D. Woodrum</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">James D. Woodrum</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Director</TD></TR>
</TABLE>
</DIV></Center>

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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>d928020dex51.htm
<DESCRIPTION>EX-5.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-5.1</TITLE>
</HEAD>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">[Packaging Corporation of America Letterhead] </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right">Exhibit 5.1 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">May&nbsp;11, 2020
</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Packaging Corporation of America </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">1 North Field Court </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Lake Forest, Illinois 60045 </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="5%" VALIGN="top" ALIGN="left">Re:</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> </P></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Ladies and Gentlemen: </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">I am providing this
letter in my capacity as Senior Vice President and General Counsel to Packaging Corporation of America, a Delaware corporation (the &#147;<U>Company</U>&#148;), in connection with the filing by the Company of a Registration Statement on Form <FONT
STYLE="white-space:nowrap">S-8</FONT> under the Securities Act of 1933, as amended (the &#147;<U>Act</U>&#148;), with the Securities and Exchange Commission covering the registration of up to 1,483,714 shares of the common stock of the Company, par
value $0.01 per share (the &#147;<U>Shares</U>&#148;), pursuant to the Packaging Corporation of America Retirement Savings Plan for Salaried Employees (the &#147;<U>Savings Plan</U>&#148;) and the Packaging Corporation of America Thrift Plan for
Hourly Employees (the &#147;<U>Thrift Plan,</U>&#148; and together with the Savings Plan, the &#147;<U>Plans</U>&#148;). </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">For purposes of
this letter, I have examined such documents, records, certificates and other instruments deemed necessary as a basis for this opinion. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Based upon and subject to the foregoing qualifications, assumptions and limitations and the further limitations set forth below, I am of the
opinion that the Shares are duly authorized and, when (i)&nbsp;the Registration Statement related to the Shares becomes effective under the Act, (ii)&nbsp;the Shares have been duly issued in accordance with the terms of the Plans upon receipt of the
consideration to be paid therefor (assuming the consideration received by the Company is at least equal to $0.01 per share), and (iii)&nbsp;the certificates or book-entry interests representing the Shares bear all necessary signatures and
authentications, the Shares will be validly issued, fully paid and nonassessable. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">I have assumed that the Company will cause certificates
or book-entry interests representing Shares issued in the future to be properly executed and delivered and will take all other actions appropriate for the issuances of such Shares. All of my opinions assume that the Registration Statement related to
the Shares will become effective under the Act before any Shares covered by such Registration Statement are sold. I have also made other assumptions which I believe to be appropriate for purposes of this letter. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">I hereby consent to the filing of this opinion with the Commission as Exhibit 5.1 to the Registration Statement. In giving this consent, I do
not thereby admit that I am in the category of persons whose consent is required under Section&nbsp;7 of the Act or the rules and regulations of the Commission. </P>
</DIV></Center>


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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This opinion is limited to the specific issues addressed herein, and no opinion may be
inferred or implied beyond that expressly stated herein. I am admitted to practice in the State of Illinois, and my opinion expressed above is subject to the qualification that I express no opinion as to the applicability of, compliance with or
effect of any laws except the General Corporation Law of the State of Delaware (including the statutory provisions, all applicable provisions of the Delaware constitution and reported judicial decisions interpreting the foregoing). I assume no
obligation to revise or supplement this opinion should the present laws of the State of Delaware be changed by legislative action, judicial decision or otherwise. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This opinion is furnished to you in connection with the filing of the Registration Statement in accordance with the requirements of Item
601(b)(5) of Regulation <FONT STYLE="white-space:nowrap">S-K</FONT> under the Act and is not to be used, circulated, quoted or otherwise relied upon for any other purpose. </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TD WIDTH="100%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Sincerely,</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">/s/ Kent A. Pflederer</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Kent A. Pflederer</TD></TR>
</TABLE></DIV>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">2 </P>

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<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>d928020dex231.htm
<DESCRIPTION>EX-23.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-23.1</TITLE>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 23.1 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Consent of Independent Registered Public Accounting Firm </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Board of Directors </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Packaging Corporation of America </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">We consent to the incorporation by reference in this registration statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> of Packaging Corporation of
America of our report dated February&nbsp;26, 2020, with respect to the consolidated balance sheets of Packaging Corporation of America as of December&nbsp;31, 2019 and 2018, the related consolidated statements of income and comprehensive income,
changes in stockholders&#146; equity, and cash flows for each of the years in the three-year period ended December&nbsp;31, 2019, and the related notes (collectively, the &#147;consolidated financial statements&#148;), and the effectiveness of
internal control over financial reporting as of December&nbsp;31, 2019, which report appears in the December&nbsp;31, 2019 annual report on Form <FONT STYLE="white-space:nowrap">10-K</FONT> of Packaging Corporation of America. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Our report refers to a change in the method of accounting for leases as of January&nbsp;1, 2019 due to the adoption of Accounting Standards Codification Topic
842, Leases. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">/s/ KPMG LLP </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chicago, Illinois </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">May&nbsp;11, 2020 </P>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 23.2 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Consent of Independent Registered Public Accounting Firm </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">To the Plan Participants and Plan Administrator of </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Packaging
Corporation of America Retirement Savings Plan for Salaried Employees: </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">We consent to the incorporation by reference in this registration statement on Form
<FONT STYLE="white-space:nowrap">S-8</FONT> of Packaging Corporation of America of our report dated June&nbsp;28, 2019, with respect to the statements of net assets available for benefits of the Packaging Corporation of America Retirement Savings
Plan for Salaried Employees as of December&nbsp;31, 2018 and 2017, the related statements of changes in net assets available for benefits for the year ended December&nbsp;31, 2018, and the related notes (collectively, the &#147;financial
statements), and the supplemental schedule of Schedule H, line 4i &#150; Schedule of Assets (Held at End of Year) as of December&nbsp;31, 2018, which report appears in the December&nbsp;31, 2018 annual report on Form
<FONT STYLE="white-space:nowrap">11-K</FONT> of the Packaging Corporation of America Retirement Savings Plan for Salaried Employees. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">/s/ KPMG LLP </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chicago, Illinois </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">May&nbsp;11, 2020 </P>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 23.3 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Consent of Independent Registered Public Accounting Firm </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">To the Plan Participants and Plan Administrator of </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Packaging
Corporation of America Thrift Plan for Hourly Employees: </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">We consent to the incorporation by reference in this registration statement on Form <FONT
STYLE="white-space:nowrap">S-8</FONT> of Packaging Corporation of America of our report dated June&nbsp;28, 2019, with respect to the statements of net assets available for benefits of Packaging Corporation of America Thrift Plan for Hourly
Employees as of December&nbsp;31, 2018 and 2017, the related statements of changes in net assets available for benefits for the year ended December&nbsp;31 2018, and the related notes (collectively, the &#147;financial statements&#148;), and the
supplemental schedules of Schedule H, Line 4a &#150; Schedule of Delinquent Participant Contributions for the year ended December&nbsp;31, 2018 and Schedule H, line 4i &#150; Schedule of Assets (Held at End of Year) as of December&nbsp;31, 2018,
which report appears in the December&nbsp;31, 2018 annual report on Form <FONT STYLE="white-space:nowrap">11-K</FONT> of the Packaging Corporation of America Thrift Plan for Hourly Employees. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">/s/ KPMG LLP </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chicago, Illinois </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">May&nbsp;11, 2020 </P>
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