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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-107413


Prospectus Supplement to Prospectus dated August 11, 2003

AvalonBay Communities, Inc.

469,114 Shares of Common Stock

        This Prospectus Supplement supplements the information we provided in our August 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.

        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 22, 2004.

        As a result of the pledge of Units owned by a Selling Stockholders identified in the prospectus dated August 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) of the table contained in such prospectus, referencing David J. Hubbard:

        The date of this Prospectus Supplement is November 22, 2004.




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Prospectus Supplement to Prospectus dated August 11, 2003 AvalonBay Communities, Inc. 469,114 Shares of Common Stock