| Sleaford to Olympia Heights (Florida) | 4,408.33 mi (7,094.52 km) |
| Sleaford to Omaha (Nebraska) | 4,226.40 mi (6,801.74 km) |
| Sleaford to On Top of the World Designated Place (Florida) | 4,313.68 mi (6,942.20 km) |
| Sleaford to Onalaska (Wisconsin) | 3,924.26 mi (6,315.49 km) |
| Sleaford to Oneida (New York) | 3,378.75 mi (5,437.57 km) |
| Sleaford to Oneonta (New York) | 3,382.82 mi (5,444.12 km) |
| Sleaford to Ontario (California) | 5,343.95 mi (8,600.25 km) |
| Sleaford to Ontario (Oregon) | 4,754.20 mi (7,651.15 km) |
| Sleaford to Opa-locka (Florida) | 4,395.78 mi (7,074.32 km) |
| Sleaford to Opelika (Alabama) | 4,256.90 mi (6,850.82 km) |
| Sleaford to Opelousas (Louisiana) | 4,630.15 mi (7,451.50 km) |
| Sleaford to Orange (California) | 5,364.32 mi (8,633.04 km) |
| Sleaford to Orange (Texas) | 4,716.39 mi (7,590.30 km) |
| Sleaford to Orange City (Florida) | 4,281.84 mi (6,890.96 km) |
| Sleaford to Orangeburg (South Carolina) | 4,035.31 mi (6,494.21 km) |
