The coastal migration hypothesis is one of two leading hypotheses about the settlement of the Americas at the time of the Last Glacial Maximum. It proposes one or more migration routes involving watercraft, via the Kurile island chain, along the coast of Beringia and the archipelagos off the Alaskan-British Columbian coast, continuing down the coast to Central and South America.

The alternative is the hypothesis solely by interior routes, which assumes migration along an ice-free corridor between the Laurentide and Cordilleran ice sheets during the Last Glacial Maximum.

The coastal migration hypothesis has been bolstered by findings such as the report that the sediments in the Port Eliza caves on Vancouver Island indicate the possibility of a survivable climate as far back 16 ka (16,000 years) in the area, while the continental ice sheets were nearing their maximum extent. Despite such research, the hypothesis is still subject to considerable debate.

Carlson, Erlandson, and others have argued for a coastal migration from Alaska to the Pacific Northwest pre-11ka (before ≈13,000 calendar years ago) that predates the hypothesized migration of Clovis people moving south through an ice-free corridor located near the continental divide. The coastal migrants may have been followed by the Clovis culture when the final retreat of the Cordilleran Ice Sheet opened migration routes between interior and coastal Alaska.

A 2017 discovery on Triquet Island by an archaeological team from the University of Victoria appears to verify local First Nation oral history traditions that the island was inhabited during the ice age. A hearth excavated at the site was determined by radiocarbon dating to be between 13,613 and 14,086 years old, making it one of the oldest settlements in North America.

While some archaeologists believe that the Clovis people moved south from Alaska through an ice-free corridor located between modern British Columbia and Alberta, recent dating of Clovis and similar Paleoindian sites in Alaska suggest that Clovis technology actually moved from the south into Alaska following the melting of the continental ice sheets at about 10.5 ka.

In North America, the earliest dog remains were found in Lawyer's Cave on the Alaskan mainland east of Wrangell Island in the Alexander Archipelago of southeast Alaska; radiocarbon dating indicates it is 10,150 years old. A genetic-based estimate indicates that this dog's lineage had split from the Siberian Zhokhov Island dog lineage 16,700 years ago. This timing coincides with the suggested opening of the North Pacific coastal route into North America.

Dating the initial coastal migration is challenging because of the flooding of early settlement sites by the rise of the eustatic sea level accompanying deglaciation. Dates for sites such as ones at Ground Hog Bay in SE Alaska (10.2 ka) and Namu, about 800 km south of Ground Hog Bay near modern Bella Coola (9.7 ka) thus represent early mainland settlement above the present-day sea level after earlier waterborne migration while the sea level was lower and the coastal mainland was still glaciated. Full understanding of the initial migration requires careful reconstruction of the land and ecological resources available to the migrants in their contemporary environment.