World's 10 Largest Bays by Surface Area

Ranked Descending

1. Hudson Bay (Canada) – 1.23 million km²
2. Baffin Bay (Canada/Greenland) – 1.15 million km²
3. Bay of Bengal (Bangladesh, India, Myanmar) – 0.86 million km²
4. Gulf of Mexico (Mexico, U.S., Cuba) – 0.77 million km²
5. Great Australian Bight (Australia) – 0.69 million km²
6. Persian Gulf (8 nations) – 0.24 million km²
7. Bay of Biscay (France, Spain) – 0.23 million km²
8. Gulf of Alaska (U.S., Canada) – 0.21 million km²
9. Gulf of Thailand (4 nations) – 0.18 million km²
10. Gulf of Guinea (13 West African nations) – 0.16 million km²

Note

"Gulf" and "bay" are often used interchangeably for large coastal indentations; this list follows common geographic convention.