<PAGE>
SMITH BARNEY INVESTMENT TRUST
On behalf of the
Smith Barney S&P 500 Index Fund
Supplement dated October 13, 1999
to the Prospectus dated March 30, 1999
The following information supplements, and to the extent inconsistent there-
with, supersedes, the information in the Prospectus under:
Annual fund operating expenses
<TABLE>
<CAPTION>
(expenses deducted from fund assets) Class A Class D
<S> <C> <C>
Management fee 0.25% 0.25%
Service (12b-1) fees 0.20% None
Other expenses 0.97% 0.93%
------ ------
Total annual fund operating expenses 1.42% 1.18%
Expense reimbursement* (0.83%) (0.79%)
------ ------
Net annual operating expenses 0.59% 0.39%
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</TABLE>
*Management has agreed to cap the fund's other expenses to 0.14% for both Class
A and Class D shares. Management may not discontinue or modify this cap without
the approval of the fund's trustees. As a result of this expense cap, the net
annual operating expenses of the fund will not exceed 0.59% for Class A shares
and 0.39% for Class D shares.
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Exchanging shares
The fund is exchangeable into the following Smith Barney
funds:
Smith Barney U.S. 5000 Index Fund
Smith Barney EAFE Index Fund
Smith Barney You should contact your Salomon Smith Barney Financial Con-
offers a sultant or dealer representative to exchange into these Smith
distinctive Barney mutual funds. Be sure to read the prospectus of the
family of Smith Barney mutual fund you are exchanging into. An exchange
Funds is a taxable transaction.
tailored to
help meet the
needs of both
large and
small
investors
.You may exchange shares only for shares of the same class.
.You must meet the minimum investment amount for each fund.
.If you hold share certificates, the transfer agent must
receive the certificates endorsed for transfer or with
signed stock powers (documents transferring ownership of
certificates) before the exchange is effective.
.The fund may suspend or terminate your exchange privilege if
you engage in an excessive pattern of exchanges.
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By telephone If you do not have a brokerage account, you may be eligible
to exchange shares through the transfer agent. You must com-
plete an authorization form to authorize telephone transfers.
If eligible, you may make telephone exchanges on any day the
New York Stock Exchange is open. Call the transfer agent at
1-800-451-2010 between 9:00 a.m. and 5:00 p.m. (Eastern
time). Requests received after the close of regular trading
on the Exchange are priced at the net asset value next deter-
mined.
You can make telephone exchanges only between accounts that
have identical registrations.
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By mail If you do not have a Salomon Smith Barney brokerage account,
contact your dealer representative or write to the transfer
agent at the address in the prospectus.
FD 01710