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Pricing Supplement No. 21 dated April 17, 1997 Registration No. 33-52571
(To Prospectus Supplement dated December 16, 1994 Rule 424(b)(3)
and Prospectus dated March 18, 1994)
BANK OF BOSTON CORPORATION
MEDIUM-TERM NOTES
DUE NINE MONTHS OR MORE FROM DATE OF ISSUE
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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 December 16, 1994, relating to Floating Rate Notes.
DTC CUSIP #: 06420MAS9
Principal Amount: $25,000,000
Issue Date (Settlement Date): April 21, 1997
Stated Maturity Date: April 21, 1998
Issue Price: 100% of Principal Amount
Agent: The First National Bank of Boston, as agent
Agent's Commission: 0
Proceeds to the
Corporation: $25,000,000.00
Interest Rate(s)
(Fixed Rate Notes): N/A
Initial Interest Rate
(Floating Rate Notes): 5.74%
Interest Payment Dates: [ ] June 15 and December 15 of each year.
[X] Other: July 21, 1997
October 21, 1997
January 21, 1998
April 21, 1998
Record Dates: [X] Fifteenth calendar day (whether or not a Business
Day) next 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
[ ] LIBOR Telerate
[ ] LIBOR Reuters
[X] 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): N/A
Index Currency
(LIBOR Notes): N/A
Designated LIBOR Page
(LIBOR Notes): N/A
Designated CMT Telerate
Page (CMT Rate Notes): N/A
Designated CMT Maturity
Index (CMT Rate Notes): N/A
Prime Rate Notes
(Floating Rate Notes): Telerate p. 125, Source FRB H.15
Spread (Plus or Minus)
(Floating Rate Notes): Minus 2.76%
Spread Multiplier
(Floating Rate Notes): N/A
Interest Rate Formula
(Floating Rate Notes): Prime Rate minus 2.76%
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Interest Reset Dates
(Floating Rate Notes): Daily (using prior day U.S. Prime Rate)
Interest Determination Dates
(Floating Rate Notes): Daily
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 April 21, 1997 to
April 21, 1998.
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
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Other Provisions: The "Interest Determination Date" with respect to the Senior
Notes offered hereby will be the Business Day immediately preceding the
applicable Interest Reset Date.
For purposes of the Senior Notes offered hereby, "Prime Rate" means, with
respect to any Prime Rate Interest Determination Date, the rate on such date as
such rate is published in H.15(519) under the heading "Bank Prime Loan." If such
rate is not published prior to 3:00 P.M., New York City time, on the related
Calculation Date, then the Prime Rate shall be the arithmetic mean of the rates
of interest publicly announced by each bank that appears on the Reuters Screen
USPRIME1 (as defined below) as such bank's prime rate or base lending rate as in
effect for such Prime Rate Interest Determination Date. If fewer than four such
rates appear on the Reuters Screen USPRIME1 for such Prime Rate Interest
Determination Date, the Prime Rate shall be the arithmetic mean of the prime
rates quoted on the basis of the actual number of days in the year divided by a
360-day year as of the close of business on such Prime Rate Interest
Determination Date by four major money center banks in The City of New York
(which may include affiliates of certain of the Agents) selected by the
Calculation Agent. If fewer than four major money center banks provide such
quotations, the Prime Rate will be determined by the Calculation Agent and will
be the arithmetic mean of four prime rates, quoted on the basis of the actual
number of days in the year divided by a 360-day year, as of the close of
business on such Prime Rate Interest Determination Date as furnished in The City
of New York by the major money center banks, if any, that have provided
quotations and as many substitute banks or trust companies as is necessary in
order to obtain four such prime rate quotations, provided such substitute banks
or trust companies are organized and doing business under the laws of the United
States, or any state thereof, each having total equity capital of at least U.S.
$500 million and being subject to supervision or examination by federal or state
authority, selected by the Calculation Agent to provide such rate or rates;
provided, however, that if the banks or trust companies selected as aforesaid
are not quoting as mentioned in this sentence, the Prime Rate determined as of
such Prime Rate Interest Determination Date shall be the Prime Rate in effect on
such Prime Rate Interest Determination Date. "Reuters Screen USPRIME1" means the
display designated as page "USPRIME1" on the Reuters Monitor Money Rates Service
(or such other page as may replace the USPRIME1 page on that service for the
purpose of displaying prime rates or base lending rates of major United States
banks).
Terms used but not defined in this Pricing Supplement shall have the
meanings specified in the above-referenced Prospectus Supplement.
