1980–81 FA Cup Third round proper Third round proper

| Tie_no | Home_team | Score | Away_team | Date_ |
|---|---|---|---|---|
| 18 | Manchester United | 2–2 | Brighton & Hove Albion | 3 January 1981 |
| Replay | Brighton & Hove Albion | 0–2 | Manchester United | 7 January 1981 |
| 19 | Norwich City | 1–0 | Cambridge United | 3 January 1981 |
| 20 | Plymouth Argyle | 1–2 | Charlton Athletic | 3 January 1981 |
| 21 | Hull City | 1–0 | Doncaster Rovers | 3 January 1981 |
| 22 | Wimbledon | 0–0 | Oldham Athletic | 3 January 1981 |
| Replay | Oldham Athletic | 0–1 | Wimbledon | 6 January 1981 |
| 23 | Huddersfield Town | 0–3 | Shrewsbury Town | 3 January 1981 |
| 24 | Mansfield Town | 2–2 | Carlisle United | 3 January 1981 |
| Replay | Carlisle United | 2–1 | Mansfield Town | 6 January 1981 |
| 25 | Port Vale | 1–1 | Enfield | 3 January 1981 |
| Replay | Enfield | 3–0 | Port Vale | 6 January 1981 |