Ilwaco (/ɪlˈwɑːkoʊ/ il-WAH-koh) is a city in Pacific County, Washington, United States.

Founded in 1890, the city was home to the Ilwaco Railway and Navigation Company along the Long Beach Peninsula, with its core economy based on logging and timber rafting.

The city is located on the southern edge of the Long Beach Peninsula, on Baker Bay on the north side of the Columbia River where it meets the Pacific Ocean.

It is near the city of Astoria, Oregon, which lies to the southeast on the southern bank of the Columbia.

Similarly to the nearby city of Astoria, Oregon, and the surrounding communities, Ilwaco historically had a significant population of Finnish immigrants.

A published photo shows the railroad's Ilwaco facilities, including a gallows turntable and elevated watering trough, were located on the southwest corner of the intersection of First and Spruce streets.

[15] This region experiences warm (but not hot), long, and somewhat dry summers, with no average monthly temperatures above 71.6 °F.

Ilwaco is home to two locations listed on National Register of Historic Places, the public recreation area of Cape Disappointment State Park, and the Colbert House, also listed as a Washington State Parks Heritage Site.

The Ilwaco freight depot survived to modern times and has been relocated to become part of the Columbia Pacific Heritage Museum.

Ilwaco's early economy was based on the extraction of natural resources, such as timber production, eventually building up as a sawmill and fishing community known for large seafood catches.

One fish processing business, in 2023, accounted for 10% of the state's non-treaty commercial harvest, but the 2024 fire at the port halved overall production in the community, leaving the city with one operational receiving facility.