Fitch Rates Fidelity Colchester Street Trust: Prime Money Market Portfolio 'AAA/V1+'

NEW YORK--(Business Wire)--
Fitch Ratings assigns a rating of 'AAA/V1+' to the Fidelity
Colchester Street Trust: Prime Money Market Portfolio, marketed under
the name Fidelity Institutional Money Market Funds: Prime Money Market
Portfolio. The assigned ratings denote the lowest expectation of
credit and market risks. The portfolio's capacity to meet its
objectives is highly unlikely to be adversely affected by foreseeable
events.

The Prime Money Market Portfolio seeks to obtain as high a level
of current income as is consistent with the preservation of principal
and liquidity within the limitations prescribed for the fund. First
launched in November 1989, the fund invests in the highest-quality
U.S. dollar denominated securities of domestic and foreign issuers,
U.S. government securities, and repurchase agreements. At the time of
the rating assignment portfolio's investments in the financial
services industries exceeded 25%.

The Prime Money Market Portfolio is invested in compliance with
industry standard regulatory requirements for money market funds with
respect to the quality, maturity, and diversification of investments
as well as with Fitch money market rating criteria. Weighted-average
maturity of the portfolio cannot exceed 60 days. Fitch surveys rated
money market portfolios on a weekly basis.

Fitch's fund rating incorporates an opinion as to investment
guidelines and practices of the portfolio's investment advisor
Fidelity Management & Research Company (FMR) and sub-advisor Fidelity
Investments Money Management, Inc.

Fitch's rating definitions and the terms of use of such ratings
are available on the agency's public site, www.fitchratings.com.
Published ratings, criteria and methodologies are available from this
site, at all times. Fitch's code of conduct, confidentiality,
conflicts of interest, affiliate firewall, compliance and other
relevant policies and procedures are also available from the 'Code of
Conduct' section of this site.

Fitch Ratings, New York
Viktoria Baklanova, CFA, 212-908-9162
Said Rafat, 212-908-0337
or
Media Relations:
Sandro Scenga, 212-908-0278

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