GMRS Guide
A red semi truck with a thin whip antenna driving down an empty two-lane prairie highway in late-afternoon sun

CB radio frequencies: all 40 channels, with the ones that matter

The full US CB chart from the FCC rule, which channels are law and which are custom, and the power and mode limits that apply to every one of them.

How we pick By , GMRS Radio Contributor · Updated · We earn a commission when you buy through our Amazon links.

US CB radio has 40 channels from 26.965 to 27.405 MHz. Channel 19 (27.185 MHz) is the highway channel, and channel 9 (27.065 MHz) is reserved by FCC rule for emergencies and traveler assistance.

Every channel allows 4 watts on AM or FM and 12 watts peak on single sideband. The full chart below comes straight from 47 CFR 95.963, read on October 13, 2026.

The CB channel chart

"FCC rule" means the use is set by regulation. "Custom" means it's a habit that varies by region and carries no legal weight.

ChFrequency (MHz)Common use
126.965
226.975
326.985
427.005Off-road clubs in many areas (custom)
527.015
627.025
727.035
827.055
927.065Emergencies and traveler assistance only (FCC rule)
1027.075Regional trucker channel in some areas (custom)
1127.085
1227.105
1327.115Marine and RV users in some areas (custom)
1427.125Common default on toy walkie-talkies (custom)
1527.135
1627.155
1727.165North-south highway traffic in some regions (custom)
1827.175
1927.185Highway and trucker channel nationwide (custom)
2027.205
2127.215Regional trucker channel in some areas (custom)
2227.225
2327.255Shared with radio-control models at up to 25 W (FCC rule)
2427.235
2527.245
2627.265
2727.275
2827.285
2927.295
3027.305
3127.315
3227.325
3327.335
3427.345
3527.355
3627.365SSB, by custom
3727.375SSB, by custom
3827.385SSB calling, usually LSB (custom)
3927.395SSB, by custom
4027.405SSB, by custom

Frequencies from 95.963. Channel 9 from 95.931; channel 23 sharing from 95.767. Customs are regional practice as described by CB retailers and Wikipedia's CB article; ask locally.

How the 40 channels are laid out

The CB band from 26.965 to 27.405 MHz Forty channel marks spaced mostly 10 kilohertz apart. Five gray marks between channels 3 and 4, 7 and 8, 11 and 12, 15 and 16, and 19 and 20 are radio-control frequencies, which is why those gaps are wider. Channels 24 and 25 sit below channel 23, between channels 22 and 26. Channels 9 and 19 are highlighted. CB band, 26.965-27.405 MHz 1919222425232640 Gray: radio-control frequencies (26.995, 27.045, 27.095, 27.145, 27.195 MHz) 24, 25, then 23
Channel 23 kept its original frequency when the band grew from 23 to 40 channels, so 24 and 25 sit just below it.

The wider gaps after channels 3, 7, 11, 15 and 19 hold radio-control frequencies from the FCC's RC rules (95.763). RC transmitters may use up to 4 watts on those five and up to 25 watts on 27.255 MHz, the same frequency as CB channel 23. That's one reason channel 23 can be noisy near RC flying fields.

Power and modes on every channel

ModeLegal limitNotes
AM4 W carrierThe traditional mode; most traffic on 19, 9 and 4
FM4 W carrierLegal since 2021; AM radios can't properly copy it
SSB (upper or lower sideband)12 W peak envelope powerNeeds SSB on both ends; customarily channels 36-40

From 95.967 (power) and 95.971 (emission types). No external amplifiers are allowed (95.939).

A radio like the Cobra 29 LTD Classic covers AM and FM. For sideband you need an SSB set such as the Uniden Bearcat 980. Our best CB radio guide compares them.

The channels that matter

Channel 9: emergencies only

This is the one channel with a legal restriction. Section 95.931 says channel 9 "may be used only for emergency communications or traveler assistance." Asking for the nearest hospital or a tow service counts as traveler assistance. Chatting doesn't. Many radios have an instant channel 9 button. Volunteer monitoring has thinned out since cell phones arrived, so if nobody answers on 9, try 19 as well.

A man in a navy work shirt chatting with another man beside a stopped minivan on a rural road at sunset
Traveler assistance, like finding a tow, is one of the two things channel 9 is legally for.

Channel 19: the highway

Truckers and road travelers share traffic and road reports here. It's busy near interstates and can be rough; the shorthand is decoded in our CB lingo and 10-codes guide.

Channel 4 and off-road groups

Many off-road clubs use channel 4 on trail runs, but clubs pick their own. Our convoy channel guide covers CB and GMRS plans for a trail group.

Channels 36-40: sideband

SSB operators gather here by custom, often on lower sideband, with channel 38 a common calling spot. An AM radio on these channels hears SSB as garbled noise.

CB rules that come up on the air

  • No license needed: CB is licensed by rule (95.305).
  • Keep conversations to five minutes, then wait at least a minute before transmitting again on that channel. Emergencies and traveler help are exempt (95.957).
  • No contacts with stations in other countries except Canadian General Radio Service stations, and no music, sound effects or advertising (95.933).
  • Use only an FCC-certified CB radio. Ham or "export" radios aren't authorized on CB channels (95.935).

A well-tuned antenna is what lets your legal 4 watts leave the truck. A meter built for 26.965-27.405 MHz, like the SURECOM SW-111, is the cheap way to check, and how to tune a CB antenna shows the steps.

CB compared with FRS and GMRS

CB sits at 27 MHz in the HF range, with long antennas and mostly AM audio. FRS and GMRS share 22 channels at 462-467 MHz with short antennas and FM. They can't talk to each other. See our FRS channel chart, the GMRS channel chart, or GMRS vs CB for off-roading if you're choosing.

Keep this handy

Memorize two numbers, 19 for the road and 9 for trouble, and put your group's own channel on a strip of tape on the radio.

Checked October 13, 2026 against eCFR 47 CFR Part 95 Subparts C and D (current to October 9, 2026): 95.931 · 95.963 · 95.967 · 95.971 · 95.763. How we research · Affiliate disclosure

Questions people ask

What frequency is CB channel 19?
27.185 MHz. Channel 19 is the common highway and trucker channel across most of the US by custom, not by FCC rule, so anyone may use it for ordinary conversation.
What is CB channel 9 used for?
Emergencies and traveler assistance only. Channel 9 is 27.065 MHz, and 47 CFR 95.931 says it may not be used for any other purpose. Volunteer monitoring of channel 9 has declined since cell phones became common, so don't count on someone listening.
Is CB radio AM or FM?
Both are legal now. CB has used AM since the start, and the FCC added FM on all 40 channels in 2021. AM and FM radios can't properly understand each other, and most traffic is still AM, so use FM only when your group agrees. SSB is the third legal mode.
Why is CB channel 23 out of order?
Channel 23 (27.255 MHz) keeps the frequency it had when CB had only 23 channels. When the band grew to 40 channels, channels 24 and 25 were placed just below it at 27.235 and 27.245 MHz. It's correct in the FCC table, not a typo.
Can a Baofeng UV-5R transmit on CB frequencies?
No. The UV-5R is a VHF/UHF radio that transmits around 144-148 and 420-450 MHz, far from CB's 27 MHz. And only FCC-certified CB radios may transmit on CB channels; ham and other non-CB transmitters aren't authorized there (47 CFR 95.935).
How many CB channels are there?
40, from 26.965 MHz (channel 1) to 27.405 MHz (channel 40), listed in 47 CFR 95.963. Single sideband uses the same 40 channels, so an SSB radio doesn't have extra channels, just different modes on each.