This post is part of GMRS Radio: The Complete Guide.
New GMRS operators usually treat all 30 channels as interchangeable. They’re not, the power limits, repeater eligibility, and bandwidth rules differ across three distinct groups.
Channels 1 to 7: Shared with FRS, Simplex Only
These are shared with Family Radio Service, meaning license-free users are on them too. GMRS stations are limited to 5 watts here and cannot use repeaters on these channels. Treat them as your general calling and short-range simplex channels.
Channels 8 to 14: Low Power Only
Capped at 0.5 watts for both GMRS and FRS users, these are the weakest channels in the band and mostly useful for very short range, like coordinating within a campsite. Don’t count on these for anything beyond talking distance.
Channels 15 to 22: The Real GMRS Channels
This is where GMRS actually does its job. These channels allow up to 50 watts and are the only ones eligible for repeater operation, meaning every GMRS repeater you’ll find is using an input/output pair from this block. If you’re setting up a base station or looking for repeater coverage, this is the range that matters.
Channels 15 to 22 Interstitials (462.5625 etc.) and 23 to 30
Wideband and narrowband splits within this range affect audio quality and legal bandwidth depending on your radio’s mode setting, worth checking your radio’s manual rather than assuming. Channels 23 to 30 are simplex-only repeater output frequencies you might hear repeater traffic on, but can’t transmit a repeater input on directly.