<SUBMISSION>
<ACCESSION-NUMBER>0001047469-04-034974
<TYPE>424B3
<PUBLIC-DOCUMENT-COUNT>1
<FILING-DATE>20041122
<DATE-OF-FILING-DATE-CHANGE>20041122
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>AVALONBAY COMMUNITIES INC
<CIK>0000915912
<ASSIGNED-SIC>6798
<IRS-NUMBER>770404318
<STATE-OF-INCORPORATION>MD
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>424B3
<ACT>33
<FILE-NUMBER>333-107413
<FILM-NUMBER>041161454
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>2900 EISENHOWER AVENUE
<STREET2>SUITE 300
<CITY>ALEXANDRIA
<STATE>VA
<ZIP>22314
<PHONE>7033296300
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>2900 EISENHOWER AVENUE
<STREET2>STE 300
<CITY>ALEXANDRIA
<STATE>VA
<ZIP>22314
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>AVALON BAY COMMUNITIES INC
<DATE-CHANGED>19980618
</FORMER-COMPANY>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>BAY APARTMENT COMMUNITIES INC
<DATE-CHANGED>19931208
</FORMER-COMPANY>
</FILER>
<DOCUMENT>
<TYPE>424B3
<SEQUENCE>1
<FILENAME>a2147152z424b3.htm
<DESCRIPTION>424B3
<TEXT>
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<P ALIGN="RIGHT"><FONT SIZE=2><B>Filed Pursuant to Rule&nbsp;424(b)(3)<BR>
Registration No.&nbsp;333-107413  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B> <A NAME="ma1917_prospectus_supplement_to_prosp__pro03926"> </A>
<A NAME="toc_ma1917_1"> </A>
<BR>    Prospectus Supplement to Prospectus dated August&nbsp;11, 2003    <BR>    <BR>    AvalonBay Communities,&nbsp;Inc.    <BR>    <BR>    469,114 Shares of Common Stock    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This Prospectus Supplement supplements the information we provided in our August&nbsp;11, 2003 Prospectus relating to 469,114 shares of our Common Stock that we
have issued or may issue in the future when we redeem limited partnership ownership interests in Avalon DownREIT V, L.P. This Prospectus Supplement is not complete without the Prospectus, and we have
not authorized anyone to deliver or use this Prospectus Supplement without the Prospectus. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In
this Prospectus Supplement, we use some capitalized terms that we defined in the Prospectus. You should read the Prospectus to understand those terms. Unless we indicate otherwise,
the information in this Prospectus Supplement is as of November&nbsp;22, 2004. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;As
a result of the pledge of Units owned by a Selling Stockholders identified in the prospectus dated August&nbsp;11, 2003, we are providing this Prospectus Supplement to update the
table under the caption "Selling Stockholders." The following supplemental information is hereby added to footnote (5)&nbsp;of the table contained in such prospectus, referencing David J. Hubbard: </FONT></P>

<UL>
<UL>

<P><FONT SIZE=2>Pursuant
to a ISDA Master Agreement and Credit Support Annex (the "ISDA Agreement") by and between David J. Hubbard, as Trustee of the David J. Hubbard Trust dated August&nbsp;27, 2001 ("Hubbard")
and Merrill Lynch, Pierce, Fenner&nbsp;&amp; Smith Incorporated ("MLPF&amp;S"), 19,096 Limited Partnership Units and underlying shares of Common Stock that are subject to this prospectus have been pledged
by Hubbard to MLPF&amp;S as security for a loan or other extension of credit to Hubbard. Upon a default under the ISDA Agreement, MLPF&amp;S, its parent, Merrill Lynch&nbsp;&amp; Co.&nbsp;Inc. or any
subsidiary thereof, may be a selling holder hereunder and upon the exchange of such Limited Partnership Units, may sell the applicable shares of Common Stock offered by this prospectus. In connection
with the foregoing, Hubbard may enter into derivative transactions with MLPF&amp;S and in connection with those derivative transactions, MLPF&amp;S may sell shares covered by this prospectus, including in
short sale transactions. If so, MLPF&amp;S may use shares pledged by or borrowed from Hubbard or others to settle those sales or to close out any related open borrowings of shares, and may
use shares received from Hubbard in settlement of such derivatives to close out any related open borrowings of stock. Hubbard may enter into option or other transactions with MLPF&amp;S that involve the
delivery of the shares offered hereby to MLPF&amp;S, who may then resell or otherwise transfer those shares using this prospectus. MLPF&amp;S or other third party in such derivative or other transactions may
be an underwriter. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
date of this Prospectus Supplement is November&nbsp;22, 2004. </FONT></P>

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<FONT SIZE=2><A HREF="#toc_ma1917_1">Prospectus Supplement to Prospectus dated August 11, 2003 AvalonBay Communities, Inc. 469,114 Shares of Common Stock</A></FONT><BR>
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