| Westmont to Orangeburg (South Carolina) | 2,139.49 mi (3,443.18 km) |
| Westmont to Orangevale (California) | 365.95 mi (588.94 km) |
| Westmont to Orchards (Washington) | 841.79 mi (1,354.72 km) |
| Westmont to Orcutt (California) | 136.80 mi (220.17 km) |
| Westmont to Oregon (Ohio) | 1,962.13 mi (3,157.75 km) |
| Westmont to Oregon (Wisconsin) | 1,673.06 mi (2,692.53 km) |
| Westmont to Oregon City (Oregon) | 819.76 mi (1,319.27 km) |
| Westmont to Orem (Utah) | 569.89 mi (917.15 km) |
| Westmont to Orinda (California) | 347.99 mi (560.03 km) |
| Westmont to Orland Park (Illinois) | 1,734.32 mi (2,791.11 km) |
| Westmont to Orlando (Florida) | 2,204.73 mi (3,548.17 km) |
| Westmont to Ormond Beach (Florida) | 2,200.06 mi (3,540.65 km) |
| Westmont to Oro Valley (Arizona) | 436.32 mi (702.19 km) |
| Westmont to Oroville (California) | 424.31 mi (682.86 km) |
| Westmont to Oshkosh (Wisconsin) | 1,730.32 mi (2,784.68 km) |
