<SEC-DOCUMENT>0001193125-20-138786.txt : 20200511
<SEC-HEADER>0001193125-20-138786.hdr.sgml : 20200511
<ACCEPTANCE-DATETIME>20200511141457
ACCESSION NUMBER:		0001193125-20-138786
CONFORMED SUBMISSION TYPE:	S-8
PUBLIC DOCUMENT COUNT:		3
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:	333-238156
		FILM NUMBER:		20864063

	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>d928001ds8.htm
<DESCRIPTION>S-8
<TEXT>
<HTML><HEAD>
<TITLE>S-8</TITLE>
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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>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">


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<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="top" 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 Amended and Restated 1999 Long-Term Incentive Plan </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><I>Copies to: </I></B></P> <P STYLE="margin-top:6pt; 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 12b-2 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">


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

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<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:0pt;margin-bottom:0pt;page-break-before:always"></P> <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 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">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">


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<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"><B>Title of securities<BR>to be registered</B></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
price</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>per share (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 price (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 Fee</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">1,400,000&nbsp;shares&nbsp;(3)&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">$132,643,000</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">$17,217.06</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>
<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 plan to reflect stock splits, stock dividends, mergers and other capital changes. </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&nbsp;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">Represents shares of Common Stock authorized for issuance under the Packaging Corporation of America Amended
and Restated 1999 Long-Term Equity Incentive Plan. </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 an additional 1,400,000 shares of our common stock, par value $0.01 per share (the
&#147;Common Stock&#148;), reserved for issuance under the Packaging Corporation of America Amended and Restated 1999 Long-Term Equity Incentive Plan (the &#147;Equity Plan&#148;). </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The increase in the number of shares authorized for issuance under the Equity Plan, as well as certain other amendments to the Equity Plan
that are described in our Definitive Proxy Statement for our 2020 annual meeting of stockholders, were approved by our stockholders at our 2020 annual meeting held on May&nbsp;5, 2020. The full text of the Equity Plan, as amended by that stockholder
approval, will be sent to employees pursuant to Rule 428(b)(1) promulgated by the Securities and Exchange Commission (the &#147;Commission&#148;) under the Securities Act of 1933, as amended (the &#147;Securities Act&#148;), and is available on the
Commission&#146;s website as an exhibit to our Definitive Proxy Statement on Schedule 14A, filed with the Commission on March&nbsp;20, 2020. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We filed a Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg.
<FONT STYLE="white-space:nowrap">No.&nbsp;333-33176)</FONT> with the Commission on March&nbsp;23, 2000 (the &#147;Original Registration Statement&#148;) covering 4,400,000 shares of our Common Stock authorized for issuance under the original version
of the Equity Plan. On June&nbsp;29, 2005, we filed an additional Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg. <FONT STYLE="white-space:nowrap">No.&nbsp;333-126215)</FONT> to register an additional 2,150,000
shares of our Common Stock pursuant to an amendment and restatement of the Equity Plan that increased the number of shares authorized for issuance under the Equity Plan, as approved by our stockholders at our 2005 annual meeting of stockholders. 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, an additional 2,000,000 shares
of our Common Stock pursuant to an amendment and restatement of the Equity Plan that increased the number of shares authorized for issuance under the Equity Plan, as approved by our stockholders at our 2009 annual meeting of stockholders. On
May&nbsp;1, 2013, we filed an additional Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Reg. <FONT STYLE="white-space:nowrap">No.&nbsp;333-188265)</FONT> to register, among other things, an additional 2,000,000 shares of
our Common Stock pursuant to an amendment and restatement of the Equity Plan that increased the number of shares authorized for issuance under the Equity Plan, as approved by our stockholders at our 2013 annual meeting of stockholders. 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="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="9%" VALIGN="top" ALIGN="left"><B>Item&nbsp;3.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Incorporation of Documents by Reference. </B></P></TD></TR></TABLE>
<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%; text-indent: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/75677/000156459020006774/pkg-10k_20191231.htm">
<FONT STYLE="white-space:nowrap">Form&nbsp;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%; text-indent: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/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%; text-indent: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/75677/000119312520056276/d884126d8k.htm">February&nbsp;28, 2020</A>, the Company&#146;s Current Report on <FONT
STYLE="white-space:nowrap">Form&nbsp;8-K/A</FONT> filed on <A HREF="http://www.sec.gov/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/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%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(d) 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"><FONT STYLE="white-space:nowrap">Form&nbsp;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 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="font-size:18pt;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="9%" VALIGN="top" ALIGN="left"><B>Item&nbsp;5.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Interests of Named Experts and Counsel. </B></P></TD></TR></TABLE>
<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 Company&#146;s 401(k) plan. </P> <P STYLE="font-size:18pt;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="9%" VALIGN="top" ALIGN="left"><B>Item&nbsp;8.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Exhibits. </B></P></TD></TR></TABLE> <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" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"><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>&nbsp;&nbsp;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Packaging Corporation of America Amended and Restated 1999 Long-Term Equity Incentive Plan (incorporated by reference herein to Appendix A to the Company&#146;s <A HREF="http://www.sec.gov/Archives/edgar/data/75677/000119312520080666/d861725ddef14a.htm">Definitive
 Proxy Statement</A> on Schedule 14A (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-15399),</FONT> filed on March&nbsp;20, 2020).</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>&nbsp;&nbsp;5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928001dex51.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>23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d928001dex231.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="d928001dex51.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">

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<TR style = "page-break-inside:avoid">
<TD WIDTH="9%" VALIGN="top" ALIGN="left"><B>Item&nbsp;9.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Undertakings. </B></P></TD></TR></TABLE>
<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
<FONT STYLE="white-space:nowrap">post-effective</FONT> 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 <FONT STYLE="white-space:nowrap">post-effective</FONT> 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, 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 <FONT STYLE="white-space:nowrap">post-effective</FONT> 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 <FONT STYLE="white-space:nowrap">post-effective</FONT> 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>

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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>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 <FONT STYLE="white-space:nowrap">Form&nbsp;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><A NAME="sig"></A>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 either 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"><U>Signature</U></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><U>Title</U></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">
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<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>
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<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>
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<TD HEIGHT="16"></TD>
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<TD HEIGHT="16" COLSPAN="2"></TD></TR>
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<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></TABLE>
</DIV></Center>


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<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>
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<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>
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<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>
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<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>
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<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>
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<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>
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</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>d928001dex51.htm
<DESCRIPTION>EX-5.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-5.1</TITLE>
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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 1,400,000 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 Amended and Restated 1999 Long-Term Equity Incentive Plan (the &#147;<U>LTIP</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 LTIP 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> <P STYLE="font-size:18pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</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 VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Sincerely,</P></TD></TR>
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<TD VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">/s/ Kent A. Pflederer</P></TD></TR>
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<TD VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Kent A. Pflederer</P></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>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>d928001dex231.htm
<DESCRIPTION>EX-23.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-23.1</TITLE>
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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 23.1 </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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