Some have pet loops. Some private have certain restrictions. Best thing to do is ask when reserving. Most state parks will show which site are pet sites.
Forest service, BLM and National Park campgrounds (generally) are; however, National Parks tend not to be dog friendly outside of the campgrounds, paved roads, or any possible noted dog areas.
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Trailer: Lifted 228BH, heavy duty springs and Yokohama tires DELAMINATED ROOF TV: 2016 GMC Sierra Z71 4x4 CC, SLT
Spare TV: Two Alaskan Malamutes
Living somewhere in ID; previously lived in Moab UT; previous to that, don't ask!