| Northampton to Ickenham | 50.19 mi (80.77 km) |
| Northampton to Ifield | 81.95 mi (131.88 km) |
| Northampton to Ilford | 62.50 mi (100.58 km) |
| Northampton to Ilfracombe | 155.10 mi (249.60 km) |
| Northampton to Ilkeston | 54.06 mi (86.99 km) |
| Northampton to Ilkley | 123.26 mi (198.36 km) |
| Northampton to Immingham | 99.64 mi (160.36 km) |
| Northampton to Ince-in-Makerfield | 115.08 mi (185.20 km) |
| Northampton to Inverness | 385.89 mi (621.03 km) |
| Northampton to Inverurie | 353.87 mi (569.49 km) |
| Northampton to Ipswich | 87.69 mi (141.13 km) |
| Northampton to Irlam | 105.40 mi (169.63 km) |
| Northampton to Irthlingborough | 13.48 mi (21.70 km) |
| Northampton to Irvine | 279.82 mi (450.32 km) |
| Northampton to Islington | 58.20 mi (93.66 km) |
