| Greenock to Odessa (Texas) | 4,697.19 mi (7,559.40 km) |
| Greenock to Ogden (Utah) | 4,495.89 mi (7,235.44 km) |
| Greenock to Oildale (California) | 5,042.00 mi (8,114.31 km) |
| Greenock to Ojus (Florida) | 4,193.06 mi (6,748.07 km) |
| Greenock to Okemos (Michigan) | 3,490.22 mi (5,616.97 km) |
| Greenock to Oklahoma City (Oklahoma) | 4,331.07 mi (6,970.19 km) |
| Greenock to Okmulgee (Oklahoma) | 4,269.70 mi (6,871.42 km) |
| Greenock to Olathe (Kansas) | 4,054.98 mi (6,525.85 km) |
| Greenock to Old Jamestown (Missouri) | 3,895.47 mi (6,269.15 km) |
| Greenock to Oldsmar (Florida) | 4,176.76 mi (6,721.85 km) |
| Greenock to Olean (New York) | 3,300.36 mi (5,311.42 km) |
| Greenock to Olive Branch (Mississippi) | 4,080.77 mi (6,567.36 km) |
| Greenock to Olivehurst (California) | 4,902.14 mi (7,889.23 km) |
| Greenock to Olney (Maryland) | 3,390.90 mi (5,457.13 km) |
| Greenock to Olympia (Washington) | 4,474.22 mi (7,200.56 km) |
