Arbuthnot Lake,[1][3] Arbuthnet Lake, or Lower Chain Lake[2][4][5] is a lake in the Mount Baker Wilderness Area, in Whatcom County, Washington, United States.

It is one of the Galena Chain lakes.

At one end of the lake is "Arbuthnot Falls".

The lake was named in 1906.

This Whatcom County, Washington state location article is a stub.