<PAGE>
Pricing Supplement No. 12 dated August 19, 1998 Registration No. 333-38135
(To Prospectus Supplement dated November 25, 1997 Rule 424(b)(3)
and Prospectus dated November 21, 1997)
BANKBOSTON CORPORATION
MEDIUM-TERM NOTES
Due Nine Months or More from Date of Issue
--------------------
Except as set forth herein, the Senior Notes offered hereby are
"Floating Rate Notes" and have such terms as are described in the accompanying
Prospectus Supplement dated November 25, 1997, relating to Floating Rate Notes.
DTC CUSIP #: 06605 TAK8
Principal Amount: $150,000,000.00
Issue Date (Settlement Date): August 24, 1998
Stated Maturity Date: August 24, 2005
Issue Price: 99.712% of Principal Amount
Interest Rate(s)
(Fixed Rate Notes): N/A
Initial Interest Rate
(Floating Rate Notes): 5.9875%
Interest Payment Dates: / / June 15 and December 15 of each year.
/x/ Other:
February 24, May 24, August 24 and November
24 of each year, or the next Business Day,
commencing November 24, 1998
Record Dates: /x/ Fifteenth calendar day (whether or not
a Business Day) immediately preceding each
Interest Payment Date.
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Interest Rate Basis / / CMT Rate
(Floating Rate Notes): / / Commercial Paper Rate
/ / Eleventh District Cost of Funds Rate
/ / Federal Funds Rate
/x/ LIBOR Telerate
/ / LIBOR Reuters
/ / Prime Rate
/ / Treasury Rate
/ / Other:
Interest Calculation
(Floating Rate Notes): /x/ Regular Floating Rate Note
/ / Floating Rate/Fixed Rate Note
Fixed Rate Commencement Date:
Fixed Interest Rate:
/ / Inverse Floating Rate Note
Fixed Interest Rate:
Index Maturity
(Floating Rate Notes): 3 Month LIBOR
Index Currency
(LIBOR Notes): U.S. Dollars
Designated LIBOR Page
(LIBOR Notes): Telerate 3750
Designated CMT Telerate
Page (CMT Rate Notes): N/A
Designated CMT Maturity
Index (CMT Rate Notes): N/A
Prime Rate Notes
(Floating Rate Notes): N/A
Spread (Plus or Minus)
(Floating Rate Notes): Plus .30%
Spread Multiplier
(Floating Rate Notes): N/A
Interest Rate Formula
(Floating Rate Notes): LIBOR +.30%
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Interest Reset Dates
(Floating Rate Notes): Quarterly, same as Interest Payment Dates
Interest Determination Dates
(Floating Rate Notes): 2 London Business Days prior to Interest
Reset Dates
Calculation Agent (if other
than the Bank)
(Floating Rate Notes): N/A
Minimum Interest Rate
(Floating Rate Notes): N/A
Maximum Interest Rate
(Floating Rate Notes): N/A
Redemption Date(s): N/A
Initial Redemption Percentage: N/A
Annual Redemption
Percentage Reduction: N/A
Holder's Optional
Repayment Date(s): N/A
Day Count Convention
(Floating Rate Notes): / / 30/360 for the period from __________ to
________________.
/x/ Actual/360 for the period from
August 24, 1998 to August 24, 2005.
Original Issue
Discount Note: / / Yes
/x/ No
Total Amount of OID: N/A
Yield to Maturity: N/A
Interest Accrual Period: N/A
Default Rate: N/A
Other Provisions: Terms used but not defined in this Pricing Supplement shall
have the meanings specified in the above-referenced Prospectus Supplement.
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DESCRIPTION OF NOTES
On August 6, 1998, the Corporation authorized an increase in the
aggregate initial offering price of Senior and Subordinated Medium-Term Notes
that may be issued and sold from time to time under the Corporation's
Medium-Term Note Program from $1,000,000,000 to $1,500,000,000, or the
equivalent thereof in one or more foreign or composite currencies. As of the
date hereof, $765,000,000 aggregate initial offering price of Senior Medium-Term
Notes had been issued, all of which are currently outstanding, and no
Subordinated Medium-Term Notes had been issued.
PURCHASE AS PRINCIPAL
This Pricing Supplement relates to $150,000,000 aggregate principal
amount of Senior Notes that are being purchased, as principal, by Chase
Securities Inc., BancBoston Securities Inc., Lehman Brothers Inc., Merrill
Lynch, Pierce, Fenner & Smith Incorporated and Salomon Brothers Inc
(collectively, the "Underwriters"). Subject to certain conditions precedent, the
Underwriters have severally but not jointly agreed to purchase from the
Corporation the respective amounts of the Senior Notes set forth opposite their
names below.
<TABLE>
<CAPTION>
Principal Amount
of Senior
Underwriter Notes
----------- ----------------
<S> <C>
Chase Securities Inc. ...................................... 30,000,000
BancBoston Securities Inc. ................................. 30,000,000
Lehman Brothers Inc. ....................................... 30,000,000
Merrill Lynch, Pierce, Fenner & Smith Incorporated.......... 30,000,000
Salomon Brothers Inc ....................................... 30,000,000
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$150,000,000
------------
------------
</TABLE>
The Underwriters have advised the Corporation that they propose
initially to offer the Senior Notes to the public at a public offering price of
99.712 percent of the principal amount (plus accrued interest, if any, from
August 24, 1998), or $149,568,000 in the aggregate. After the initial public
offering, the public offering price, concession and discount may be changed.
The Underwriters will purchase the Senior Notes from the Corporation at
the public offering price, less a discount of .625 percent of the principal
amount, or $937,500 in the aggregate. Accordingly, the net proceeds payable by
the Underwriters to the Corporation from the sale of the Senior Notes will be
99.087% of the principal amount, or $148,630,500, before deduction of expenses
payable by the Corporation.
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