Steam locomotives operated in the United Kingdom with names beginning with J.
| Name | Railroad | Builder, s/n | Build date | Whyte type | Notes |
|---|---|---|---|---|---|
| Jackdaw | GWR 3447 | 4-4-0 | |||
| Jamaica | LMS 5612 | 4-6-0 | |||
| James Fitzjames | LNER 6401 | 4-4-0 | |||
| Janus | GWR | 0-6-0 | |||
| Jason | GWR | 0-6-0 | |||
| Javelin | GWR | 2-2-2 | |||
| Jay | SDR | 0-4-0ST | |||
| Jean | Krauss-Maffei | 0-4-0 | 1926 | Ex-RH&DR #4 The Bug; returned to RH&DR in the 1970s. | |
| Jeanie Deans | LNER 9899 | 4-4-0 | |||
| Jellicoe | LMS 5667 | 4-6-0 | |||
| Jersey | SR 81 | 4-4-0 | |||
| Jervis | LMS 5663 | 4-6-0 | |||
| Jingling Geordie | LNER 9421 | 4-4-0 | |||
| Joffre | LNER 9682 | 0-6-0 | |||
| John Bunyan | BR 70003 | Crewe | 3/1951 | 4-6-2 | Withdrawn March 1967; scr December 1967. |
| John Gray | GWR | 2-4-0 | |||
| John Milton | BR 70005 | Crewe | 4/1951 | 4-6-2 | Wd 7/1967; scr 1/1968. |
| John of Gaunt | BR 70012 | Crewe | 6/1951 | 4-6-2 | Wd 12/1967; scr 4/1968. |
| Jonathan Oldbuck | LNER 6383 | 4-4-0 | |||
| Joyous Gard | BR 73088 | Derby | 9/1955 | 4-6-0 | Wd 10/1966; scr 6/1967. |
| Joyous Gard | SR 741 | 4-6-0 | |||
| Juno | GWR | 0-6-0ST | |||
| Juno | SDR | 0-6-0ST | |||
| Jupiter | GWR | 2-2-2 | |||
| Jupiter | GWR 3313 | 4-4-0 | |||
| Jutland | LMS 5684 | 4-6-0 | |||
| Jutland | LNER 5504 | 4-4-0 | |||
| Juvenal | GWR | 4-4-0ST |