It flows generally west to Willapa Bay, an estuary of the Pacific Ocean.

The North Fork originates a couple miles west of South Bend, near the source of the Bone River.

It flows in a curving path southwest then north, less than a mile from the coast, to join the other forks in the Palix estuary.

It originates in the Willapa Hills and flows generally west and northwest through hilly terrain.

[3] According to Edmond S. Meany the river's name, which he spelled "Palux", comes from the Chehalis language and means "slough covered with trees".