<PAGE>
Rule 497(e)
33-26305
BLACKROCK FUNDS SM
THE BOND PORTFOLIOS/INVESTOR CLASSES
SUPPLEMENT TO PROSPECTUS DATED JANUARY 28, 1999
BlackRock Low Duration Bond Portfolio
Fund Management
The section "Fund Management" on page 8 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Scott Amero, Managing Director of BFM since
1990, Keith Anderson, Managing Director of BFM since 1988 and Rajiv Sobti,
Managing Director of BFM since March 1998. Prior to joining BFM, Rajiv
Sobti was a Managing Director and head of Quantitative Research with Don-
aldson Lufkin & Jenrette for 12 years. Scott Amero has been a member of the
team managing the fund since 1992, Keith Anderson since 1992 and Rajiv
Sobti since 1998. Scott Amero has been a portfolio co-manager since incep-
tion, Keith Anderson since 1999 and Rajiv Sobti since 1999.
BlackRock Intermediate Government Bond Portfolio
Fund Management
The section "Fund Management" on page 15 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Scott Amero, Managing Director of BFM since
1990, Keith Anderson, Managing Director of BFM since 1988 and Rajiv Sobti,
Managing Director of BFM since March 1998. Prior to joining BFM, Rajiv
Sobti was a Managing Director and head of Quantitative Research with Don-
aldson Lufkin & Jenrette for 12 years. Scott Amero has been a member of the
team managing the fund since 1995, Keith Anderson since 1995 and Rajiv
Sobti since 1998. Scott Amero has been a portfolio co-manager since 1995,
Keith Anderson since 1999 and Rajiv Sobti since 1999.
BlackRock Intermediate Bond Portfolio
Fund Management
The section "Fund Management" on page 22 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Scott Amero, Managing Director of BFM since
1990, Keith Anderson, Managing Director of BFM since 1988 and Rajiv Sobti,
Managing Director of BFM since March 1998. Prior to joining BFM, Rajiv
Sobti was a Managing Director and head of Quantitative Research with Don-
aldson Lufkin & Jenrette for 12 years. Scott Amero has been a member of the
team managing the fund since 1995, Keith Anderson since 1995 and Rajiv
Sobti since 1998. Scott Amero has been a portfolio co-manager since 1995,
Keith Anderson since 1999 and Rajiv Sobti since 1999.
<PAGE>
BlackRock Core Bond Portfolio
Fund Management
The section "Fund Management" on page 29 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Keith Anderson, Managing Director of BFM
since 1988, Scott Amero, Managing Director of BFM since 1990 and Rajiv
Sobti, Managing Director of BFM since March 1998. Prior to joining BFM,
Rajiv Sobti was a Managing Director and head of Quantitative Research with
Donaldson Lufkin & Jenrette for 12 years. Keith Anderson has been a member
of the team managing the fund since 1997, Scott Amero since 1992 and Rajiv
Sobti since 1998. Keith Anderson has been a portfolio co-manager since
1997, Scott Amero since 1999 and Rajiv Sobti since 1999.
BlackRock Government Income Portfolio
Fund Management
The section "Fund Management" on page 36 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Rajiv Sobti, Managing Director of BFM since
March 1998 and Andrew Phillips, Managing Director of BFM since 1991. Prior
to joining BFM, Rajiv Sobti was a Managing Director and head of Quantita-
tive Research with Donaldson Lufkin & Jenrette for 12 years. Rajiv Sobti
has been a member of the team managing the fund since 1998 and Andrew Phil-
lips since 1995. Both have been portfolio co-managers since 1999.
BlackRock GNMA Portfolio
Fund Management
The section "Fund Management" on page 44 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Rajiv Sobti, Managing Director of BFM since
March 1998 and Andrew Phillips, Managing Director of BFM since 1991. Prior
to joining BFM, Rajiv Sobti was a Managing Director and head of Quantita-
tive Research with Donaldson Lufkin & Jenrette for 12 years. Rajiv Sobti
and Andrew Phillips have been members of the team managing the fund since
1998 and portfolio co-managers since 1999.
BlackRock Managed Income Portfolio
Fund Management
The section "Fund Management" on page 50 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Keith Anderson, Managing Director of BFM
since 1988, Scott Amero, Managing Director of BFM since 1990 and Rajiv
Sobti, Managing Director of BFM since March 1998. Prior to joining BFM,
Rajiv Sobti was a Managing Director and head of Quantitative Research with
Donaldson
2
<PAGE>
Lufkin & Jenrette for 12 years. Keith Anderson has been a member of the
team managing the fund since 1997, Scott Amero since 1990 and Rajiv Sobti
since 1998. Keith Anderson has been a portfolio co-manager since 1997,
Scott Amero since 1999 and Rajiv Sobti since 1999.
BlackRock International Bond Portfolio
Fund Management
The section "Fund Management" on page 58 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Andrew Gordon, Managing Director of BFM
since 1996 and Keith Anderson, Managing Director of BFM since 1988. Prior
to joining BFM, Andrew Gordon was responsible for non-dollar (internation-
al) research at Barclay Investments from 1994 to 1996 and at CS First Bos-
ton from 1986 to 1994. Andrew Gordon has been a member of the team managing
the fund since 1997 and Keith Anderson since 1996. Andrew Gordon has been a
portfolio co-manager since 1997 and Keith Anderson since 1999.
BlackRock High Yield Bond Portfolio
Fund Management
The section "Fund Management" on page 66 has been amended to read in its
entirety as follows:
The fund is managed by a team of investment professionals at BlackRock
Financial Management, Inc. (BFM), including the following individuals who
have day-to-day responsibility: Dennis Schaney and Michael Buchanan. Dennis
Schaney is co-leader of the High Yield Team and a Managing Director of BFM
since February 1998. Prior to joining BFM, he was a Managing Director in
the Global Fixed Income Research and Economics Department of Merrill Lynch
for nine years. Michael Buchanan, co-leader of the High Yield Team, has
served as Director of BFM since June 1998. Prior to joining BFM, Michael
Buchanan was Vice President of Investments at Conseco Capital Management
where he was a portfolio manager responsible for high yield debt, bank
loan, and emerging markets debt trading. Dennis Schaney and Michael
Buchanan have been members of the team managing the fund since inception.
Dennis Schaney has been a portfolio co-manager since inception and Michael
Buchanan since 1999.
Annual Fund Operating Expenses
The footnote to the Annual Fund Operating Expenses table regarding waivers for
each of the funds appearing on pages 8, 15, 21, 28, 35, 43, 50, 57, 65, 72, 81,
89, 97, 105 and 113 has been amended to read in its entirety as follows:
BlackRock has contractually agreed to waive or reimburse fees or expenses
in order to limit certain (but not all) fund expenses for the next year.
The fund may have to repay these waivers and reimbursements to BlackRock in
the following two years if the repayment can be made within these expense
limits. In addition, BlackRock Distributors, Inc., the fund's distributor,
has contractually agreed to waive 12b-1 distribution fees on Investor A
Shares in the amount of .095% of average daily net assets (otherwise pay-
able at the maximum annual rate of .10% of average daily net assets) for
the next year. "Net Expenses" in the table have been restated to reflect
these waivers and reimbursements.
3
<PAGE>
The section "Purchase of Investor B Shares" on page 120 is amended by adding
the following after the chart:
Investor B Shares of the Intermediate Government Bond and Managed Income
Portfolios purchased from December 1, 1999 to December 31, 1999 are subject
to a CDSC at the rates shown in the chart below:
<TABLE>
<CAPTION>
CONTINGENT DEFERRED SALES
NUMBER OF YEARS CHARGE (AS % OF DOLLAR AMOUNT
ELAPSED SINCE PURCHASE SUBJECT TO THE CHARGE)
---------------------- -----------------------------
<S> <C>
Up to one year 3.50%
More than one but less than two years 3.00%
More than two but less than three years 2.00%
More than three but less than four years 1.00%
More than four years 0.00%
</TABLE>
This supplement is dated November 22, 1999.
4
