PROSPECTUS SUPPLEMENT                                         File No. 333-38792
- ---------------------                                             Rule 424(b)(3)
(To Prospectus Supplement and Prospectus dated
June 16, 2000 and June 15, 2000, respectively)
Prospectus number:      2049


                             Merrill Lynch & Co., Inc.
                           Medium Term Notes, Series B
                   Due Nine Months or More from Date of Issue


                               Floating Rate Notes


Principal Amount:  $20,000,000         Original Issue Date:    December 1, 2000

CUSIP Number:      59018Y CR0          Stated Maturity Date:   December 1, 2003

Interest Calculation:                  Day Count Convention:
- ---------------------                  ---------------------
[X]  Regular Floating Rate Note        [X]  Actual/360

[ ]  Inverse Floating Rate Note        [ ]  30/360

       (Fixed Interest Rate):          [ ]  Actual/Actual

Interest Rate Basis:
- --------------------
[X]  LIBOR                             [ ]  Commercial Paper Rate

[ ]  CMT Rate                          [ ]  Eleventh District Cost of Funds Rate

[ ]  Prime Rate                        [ ]  CD Rate

[ ]  Federal Funds Rate                [ ]  Other (see attached)

[ ]  Treasury Rate
   Designated CMT Page:                Designated LIBOR Page:
        CMT Telerate Page:                  LIBOR Telerate Page:  3750
        CMT Reuters Page:                   LIBOR Reuters Page:


Index Maturity:         Three Months      Minimum Interest Rate:  Not Applicable

Spread:                 0.2500%           Maximum Interest Rate:  Not Applicable

Initial Interest Rate:  TBD               Spread Multiplier:      Not Applicable

Interest Reset Dates:      Quarterly, on the 1st of every March, June, September
                           and December,  commencing  March 1, 2001,  subject to
                           modified following business day convention.

Interest Payment Dates:    Quarterly, on the 1st of every March, June, September
                           and December,  commencing  March 1, 2001,  subject to
                           modified following business day convention.

Repayment at the
Option of the  Holder:     The  Notes  cannot  be  repaid  prior  to the  Stated
                           Maturity Date.

Redemption at the
Option of the Company:     The Notes  cannot  be  redeemed  prior to the  Stated
                           Maturity Date.

Form:                      The  Notes  are  being  issued  in  fully  registered
                           book-entry form.

Trustee:                   The Chase Manhattan Bank

Dated:                     November 28, 2000