<PAGE>
RULE NO. 424(b)(3)
REGISTRATION NO. 333-64463
Prospectus Supplement No. 4 dated September 24, 1999
to the Prospectus (the "Prospectus") of
United Rentals, Inc. (the "Company") and United Rentals Trust I,
dated January 20, 1999
(included in Registration Statement on Form S-3,
Registration No. 333-64463)
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The entities or persons listed below are considered Selling Holders for
purposes of the Prospectus with respect to the indicated numbers of Preferred
Securities beneficially owned by each such Selling Holder and shares of Common
Stock currently issuable upon conversion of such Preferred Securities. The
Prospectus covers all securities shown in the table below (and any Debentures
acquired in exchange therefor). In certain cases, the indicated Preferred
Securities may be held of record by a nominee or custodian for the account of
the Selling Holder. The indicated number of shares of Common Stock issuable
upon conversion of the Preferred Securities is subject to adjustment in ceratin
circumstances as described in the Prospectus. Capitalized terms used herein and
not defined herein have the meanings set forth in the Prospectus.
<TABLE>
<CAPTION>
# of Shares
# of Preferred Issuable upon
Securities Conversion of
Selling Holder Owned Pref. Securities
- -------------- ----- ----------------
<S> <C> <C>
AIM VI Balance Fund 500 572
Banc of America Securities LLC (1) (2) 25,500 29,221
BT Capital Mutual Fund -- Capital Appreciation (3) 6,200 7,104
BT Equity Mutual Funds -- Equity Appreciation Fund (3) 40,200 46,066
BT Pyramid Fund -- Capital Appreciation Fund (3) 53,200 60,963
Deephaven Domestic Convertible Trading Ltd. 17,200 19,709
Deutsche Bank Securities (1)(4)(5) 141,750 162,435
Goldman Sachs and Company (1) (5) 26,600 30,481
Merrill Lynch Safekeeping (2) 99,600 114,134
Northwestern Mutual Life Insurance Company 115,000 131,781
Northwestern Mutual Life Insurance Company Group Annuity 10,000 11,459
Oppenheimer Aggressive Growth Fund VA 100,000 114,593
Oppenheimer Convertible Securities Fund (1) 75,000 85,944
Oppenheimer Equity Income Fund 110,000 126,052
Oppenheimer Midcap Fund 10,000 11,459
Paloma Strategic Securities Limited 135,000 154,700
</TABLE>
<PAGE>
<TABLE>
<S> <C> <C>
Reliant Trading 15,334 17,571
Shepherd Trading Limited 6,312 7,233
TCW Group, Inc. 288,500 330,600
</TABLE>
(1) The securities shown in the table with respect to the indicated Selling
Holder are in addition to the securities shown with respect to this Selling
Holder in the Prospectus to which this supplement relates and/or previous
supplements thereto.
(2) The indicated Selling Holder (or its affiliates) has, from time to time,
provided investment banking services to the Company for which the Selling
Holder was paid customary compensation.
(3) An affiliate of the indicated Selling Holder was one of the initial
purchasers of the Preferred Securities from the Issuer and was paid
customary compensation in connection with the distribution of such
securities.
(4) The indicated Selling Holder (or its affiliates) has, from time to time,
provided certain financing to the Company.
(5) The indicated Selling Holder was one of the initial purchasers of the
Preferred Securities from the Issuer and was paid customary compensation in
connection with the distribution of such securities. In addition, the
indicated Selling Holder (or its affiliates) has, from time to time,
provided, and may in the future provide, other investment banking services
to the Company for which the Selling Holder was or will be paid customary
compensation.
