The list of ship commissionings in 1864 is a chronological list of ships commissioned in 1864. In cases where no official commissioning ceremony was held, the date of service entry may be used instead.
| Date | Operator | Ship | Pennant | Class and type | Notes |
|---|---|---|---|---|---|
| 7 April |  United States Navy | Saugus | – | Canonicus-class monitor | Commissioned at Philadelphia Navy Yard, Philadelphia,, Pennsylvania, with Commander Edmund R. Colhoun in command [1] |
| 16 April | United States Navy | Canonicus | – | Canonicus-class monitor | Commissioned at Boston, Massachusetts, with Commander E. G. Parrott in command [2] |