311 campgrounds with first-come sites in Idaho

Most are run by the Forest Service. The two with the most are Boise National Forest and Sawtooth National Forest. Sizes are lopsided, from 1 site at the small end to 71 at the large.

A campground is listed when Recreation.gov or the Forest Service records it as first-come, first-served. Campgrounds where some sites book online and the rest are first-come are listed too, marked partly reservable.