The meridian 48° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Greenland, the Atlantic Ocean, South America, the Southern Ocean, and Antarctica to the South Pole.
The 48th meridian west forms a great circle with the 132nd meridian east.
The map indexing scheme of Canada's National Topographic System begins in the east at the 48th meridian west.
Starting at the North Pole and heading south to the South Pole, the 48th meridian west passes through:
| Co-ordinates | Country, territory or sea | Notes |
|---|---|---|
| Arctic Ocean | ||
| Lincoln Sea | ||
| John Murray Island | ||
| Lincoln Sea | ||
| Victoria Fjord | ||
| Wulff Land | ||
| Atlantic Ocean | ||
| Pará Maranhão — from Tocantins — from Goiás — from Federal District — from, passing just west of Brasilia (at) Goiás — from Minas Gerais — from São Paulo — from | ||
| Atlantic Ocean | ||
| Southern Ocean | ||
| Antarctica | Claimed by both (Argentine Antarctica) and (British Antarctic Territory) | |