| Wellingborough to Smolyan | 1,397.11 mi (2,248.43 km) |
| Wellingborough to Sofia | 1,293.78 mi (2,082.14 km) |
| Wellingborough to Sopot | 1,352.22 mi (2,176.19 km) |
| Wellingborough to Sozopol | 1,480.84 mi (2,383.18 km) |
| Wellingborough to Sredets | 1,463.38 mi (2,355.08 km) |
| Wellingborough to Stamboliyski | 1,366.07 mi (2,198.47 km) |
| Wellingborough to Stara Zagora | 1,397.46 mi (2,248.99 km) |
| Wellingborough to Svilengrad | 1,448.29 mi (2,330.80 km) |
| Wellingborough to Svishtov | 1,336.10 mi (2,150.24 km) |
| Wellingborough to Targovishte | 1,401.08 mi (2,254.82 km) |
| Wellingborough to Teteven | 1,321.56 mi (2,126.85 km) |
| Wellingborough to Troyan | 1,340.95 mi (2,158.05 km) |
| Wellingborough to Tryavna | 1,373.06 mi (2,209.72 km) |
| Wellingborough to Tutrakan | 1,370.64 mi (2,205.84 km) |
| Wellingborough to Varna | 1,456.90 mi (2,344.65 km) |
