Nghệ An is a coastal province near the northernmost part of the North Central Coast region, Central Vietnam. It borders Thanh Hóa to the north, Hà Tĩnh to the south, Xiangkhouang, Bolikhamsai and Houaphan of Laos to the west, and the East Sea to the east.

Thanh Hóa is the northernmost coastal province in the North Central Coast region of Central Vietnam. It borders Sơn La, Hòa Bình, and Ninh Bình to the north, Nghệ An to the south, the Laotian province of Houaphanh to the west with a boundary of over 192 kilometres (119 mi) long, and the South China Sea to the east.