The meridian 80° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Atlantic Ocean, the Caribbean Sea, Panama, South America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole. In Antarctica, the meridian defines the western limit of the British territorial claim and passes through the Chilean claim - the two claims overlap. The 80th meridian west forms a great circle with the 100th meridian east.

From Pole to Pole

Starting at the North Pole and heading south to the South Pole, the 80th meridian west passes through: ! scope="col" width="120" | Co-ordinates ! scope="col" | Country, territory or sea ! scope="col" | Notes ! scope="row" style="background:#b0e0e6;" | Arctic Ocean ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Jones Sound ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Baffin Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Eclipse Sound ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Murray Maxwell Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Foxe Basin ! scope="row" style="background:#b0e0e6;" | Foxe Channel ! scope="row" style="background:#b0e0e6;" | Hudson Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Hudson Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Hudson Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Hudson Bay ! scope="row" style="background:#b0e0e6;" | James Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | James Bay ! scope="row" | 🇨🇦 ! scope="row" style="background:#b0e0e6;" | Lake Erie ! scope="row" | 🇺🇸 ! scope="row" style="background:#b0e0e6;" | Atlantic Ocean ! scope="row" | 🇨🇺 ! scope="row" style="background:#b0e0e6;" | Caribbean Sea ! scope="row" | 🇰🇾 ! scope="row" style="background:#b0e0e6;" | Caribbean Sea ! scope="row" | 🇵🇦 ! scope="row" style="background:#b0e0e6;" | Gulf of Panama ! scope="row" | 🇵🇦 ! scope="row" style="background:#b0e0e6;" | Pacific Ocean ! scope="row" | 🇪🇨 ! scope="row" | 🇵🇪 ! scope="row" style="background:#b0e0e6;" | Pacific Ocean ! scope="row" style="background:#b0e0e6;" | Southern Ocean ! scope="row" | Antarctica