The meridian 40° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Asia, Africa, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole. The meridian is used in some contexts to delineate Europe or what is associated with the continent of Europe as an easternmost limit, e.g. to qualify for membership of the European Broadcasting Union.
The 40th meridian east forms a great circle with the 140th meridian west.
Starting at the North Pole and heading south to the South Pole, the 40th meridian east passes through:
| Co-ordinates | Country, territory or sea | Notes |
|---|---|---|
| Arctic Ocean | ||
| Barents Sea | ||
| Island of Ostrov Lumbovskiy and the Kola Peninsula | ||
| White Sea | ||
| White Sea | Dvina Bay | |
| For about 10km | ||
| For about 6km | ||
| Passing east of Adler, less than a kilometer west of the border with (at) | ||
| Black Sea | ||
| Red Sea | ||
| Dahlak Archipelago and the mainland | ||
| Indian Ocean | Passing just east of the islands of Pemba, Latham and Mafia, | |
| Indian Ocean | Passing between the atoll of Bassas da India and Europa Island, | |
| Southern Ocean | ||
| Antarctica | Queen Maud Land, claimed by | |