CB Radio Frequencies & Channels (PDF)

By: Jeremy Neisser

CB Radio has 40 channels with CB radio frequencies ranging from 26.965 to 27.405 MHz. Channels are generally spaced 10 MHz apart. The CB frequencies are listed in the table below. I have included different sets of channels used by people in various countries around the world.

As you can see, these CB radio channels overlap each other, which is intentional so that more than one person can use a channel at the same time without interfering with each other.

The actual frequency on which a conversation takes place is determined by the software on the radio.

When one radio transmits on a cb channel, all the other radios tuned to that channel will move off-frequency by a small amount so as not to interfere with the transmitted signal.

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What are the CB radio frequencies?

Download the PDF here

Are CB radios AM or FM? -

The CB radio spectrum is AM - Amplitude Modulation. You can hear the difference in sound quality between FM and AM on your local FM stations when a thunderstorm gets too close to the transmitter.

Understand that there are two "worlds" of channels. UHF (Ultra High Frequency) and VHF (Very High Frequency). UHF channels were channels 14 through 40, and VHF channels were 1 - 13. Channels 30, 31 and 32 are 2 meter ham radio repeater outputs (operate in the 70cm band).

The original 26 "mid-band" UHF CB channels that start at channel 14 are now on the 446 MHz service. There were originally 40 VHF low-band (1 to 6 MHz) and 20 UHF high band (ultra high frequency, 300 kHz - 3 MHz) channels in total.

The use of the original 29 VHF + 21 UHF was later reduced to only 14 "mid-band" UHF CB radio channels (14 through 28). In late 1979 the FCC removed channels 1 - 13 from the 40 channel CB band plan.

In 1981, in an effort to increase highway traffic safety, 14 UHF CB radio channels became "highway" channels (29 through 42) and 11 UHF CB channels were "intermediate" CB channels (50 through 59). In October 1983 it was further ruled that these CB channels could be used by individuals on two-way radios in their cars only while driving (hands-free), and then only during periods when the vehicle was actually being operated or was required to be equipped with an operable two-way radio.

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What band should CB radio be on? -

There is no "best" band. CB radio operators can be found on one or another of the 40 channels, depending on what they are trying to do.

It really depends on where you are located in the world and what other services exist there as well. Generally speaking, channel 1 is the most popular cb channel and 13 is the least used because it doesn't overlap with any VHF radio service.

CB radio Channel 11 is also very rarely used due to its proximity to an amateur (ham) radio repeater output frequency (channel 1).

The majority of highway/truck drivers operate around channels 5 and 11, while many boaters use channels 16 through 22 for local communications within their immediate area.

A lot of people have scanners that let them receive any channel that they like, or they may own more than one radio so that they can monitor several channels at the same time.

You just need to be able to get a signal on your specific scanner from that other party you are trying to communicate with.

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For example, West Coast boaters use 21 and 22 which are clear of any ham user. In states such as Florida, Texas, and California where there is a lot of back and forth between boats in close proximity Channel 16 is used extensively due to its proximity to the marine band.

Boat captains call each other on channel 16 - 17 (as well as channel 9) all day long relaying position reports or leaving a voice mail for their buddies who might not be tuned in yet. Sometimes you can be in a harbor and have 20 radios going off all around you with channel 16 being the most popular.

No matter what channel they are on, everyone listens to channel 19 from time to time just for fun. It's a free-for-all where anyone can "Try CB radio For Free".

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What is "Freebanding" ? -

Freebanding; or Freeband CB'ing refers to the practice of communicating outside your license privileges by using modified channels above or below your frequency allocation. This includes any use which exceeds that allowed by the FCC for communication on the 26/27 MHz band, such as listening to or transmitting between FM radio stations (87.9 through 107.1), scanning services, television weather spots, broadcast stations, and other signals.

Transmitting between channels is called "hopping" or "chirping". It was once legal for non-amateur radio service users to use only five specific channels above and below those allocated, but this exemption was eliminated by the 1999 FCC ruling.

Freebanding is a big issue indeed! Channel 19 is always full of vehicles (called 'stuck mikes'), who are innocently enjoying their new toy. They always seem to be using channel 19 to practice, asking questions, and such.

The problem with CB radios today, in my eyes anyway, is that many people don't know when to get off when they have no business being on the air in the first place.

They transmit way too much information for their own good. If they don't go to school on channel 19, then they are using other freeband CB frequencies to discuss subjects that should be discussed in the family vehicle or at home.

Freebanding is usually not used for criminal activities such as drug deals or pornography; but rather people who just want to talk without any worries of someone saying "What are you doing?" if they can hear them over their scanner listening to someone else who might have more information than what is being broadcast.

Some do it because they think that the government is listening and will try and find out where they live by scanning down below channels 1-5. In reality, law enforcement agencies rarely monitor outside these channels unless there are crimes taking place on one of those frequencies. Some do it for the thrill of breaking a law, even if they are not guilty of anything except talking on the radio.

Freebanding is illegal! -

It's hard to believe that there are people out there who will argue otherwise considering the number of times this has been upheld in court and over so many years.

In 1969 the United States Court of Appeals for the District of Columbia Circuit (also known as "The D.C. Circuit") ruled in favor of FCC rules prohibiting unlicensed operation above channel 5 because such usage interferes with licensed users' communication and their assigned frequencies could be used by others more qualified than CB operators.

What is Channel 9 on a CB? How to use it?

Most CB radios include channel 9 which is a broadcast function. It differs from the other cb radio frequencies in that it transceivers on a rotating cycle of each frequency in every 10-second interval. So when you are tuned to channel 9, you will hear all the other channels for one second each rotation (a complete spectrum sweep).

Channel 9 can be used as an alternative voice frequency during times of poor radio signal conditions or heavy interference (QRM) on your usual calling frequency.

Keep in mind though that many modern radios no longer receive this channel due to its low output power and high harmonic content. If your radio doesn't have a dedicated connector for it, plugging in a microphone into the microphone jack would probably allow access to channel 9.

Channel 9 can also be used as a scanning method for emergency communications (if you are into Ham radio, for example). When a channel is constantly transmitting, it can become noisy and hard or impossible to hear. Channel 9 allows you to always have access to the widest possible range of channels with your CB radio without actually having to change any dials or switches.

Here's how it works: when you're listening to channel 9 and an emergency call comes in on another relative frequency, simply switch over to that other frequency [before the end of its one-second transmission] and tune back down after it has been completed (or stopped).

This sounds simple enough but keep in mind that since channel 9 transmits everything else in sequence (rotating through each voice channel twice per minute), you must listen to the entire sequence before manually switching frequencies. This is only applicable for analog radios with channel 9 as a broadcast of other channels.

Digital radios do not have this capability.

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What is the maximum wattage for a CB radio?

The FCC restricts all AM transmissions to 4 watts legal limit on the 40 channel marine band. On the 11 channel truckers channels, you can run up to 12W of power (25% over the max). Anything higher is considered illegal CB radio operation and should be avoided for obvious reasons.

CB Radio Frequency Chart: Which Frequency is Which Channel?

I put together the CB frequency and CB channel chart in an easy to download PDF. 

Here is the history behind CB radio frequencies:

The original 26 "Mid-Band" channels with a frequency of around 27 MHz (26.965 MHz to 27.405 MHZ) were assigned in 1946 by the FCC, for use by persons with Citizen's Band Radio stations that operated under Part 90 of FCC rules and regulations, also known as WAS or General Mobile Radio Service. The citizens band service started in 1945, with the first transmissions made on 27 February of that year.

The first channel was 26.965 MHz and the last one was 27.405 MHz. There were 22 channels (mid-band), each spaced exactly 10 kHz apart from its nearest neighbor, as you can see in the table below. For example, channel 26 was 27.065 MHz and channel 27 was 27.105 MHz. There were 40 channels in total in 1946/47.

Tom Brown of Motorola developed a "high-band" expansion to the 10 channels of mid-band CB - between 30 and 31 MHz (27777 kHz), which was implemented in 1961. In May 1973 the FCC further expanded the CB radio band plan to 40 channels (a new channel on 30 MHz at 30000 kHz, was added). The channels were spaced 5 kHz apart (a gap of 5kHz was left between each frequency pair).

The mid-band channels were frequencies 1 through 10, and 15 through 22. The high-band expansion added frequencies 11 through 14 and 23 - 40.

The FCC expanded the CB radio Band plan to an even 50 channels by the addition of 12 channels at 446 MHz in February 1982. Channels 30, 31 and 32 are 2 meter ham radio repeater outputs (operate in the 70cm band). The 26 "mid-band" channels were removed from the 40 channel CB band plan. They are now on the 446 MHz service, but are not part of a CB radio system.

In July 1987, the FCC further expanded the high-band to 83 channels (frequency spacing 5 kHz), plus one shared transmitter site at 26.965 MHz and 12 shared transmitter sites at 446.0125 MHz, for a total of 94 channels in all.

This added channels 41 through 83 and shared repeater outputs (channels 30 - 32). Channel 23 was deleted from the expanded high-band plan.

Channel 9 is 446.000 MHz Output frequency on many CB radios. Most newer radios have channel 9 as a priority channel (the radio tries to maintain carrier on channel 9).

Around 1990 the FCC authorized two-way radios for use with CB radios to transmit on 446.0275 MHz (referred to as Sub-Band "D"). This was done in response to the fact that many citizens band users were moving away from using CB radios, and onto using mobile two-way radios that were authorized for Part 90 Subpart D.

Since then several other sub-bands have been authorized for use with CB radios. These include 446.0125 MHz (Sub-Band "C"), which was added in July 1987, as well as 446.025 MHz (Sub-Band "B"), and 446.0375 MHz (Subband "A").

The current FCC rules for Citizens Band Radio Service are Part 95, subpart D, which was added to the Code of Federal Regulations as of July 1st 1993. Sub-Band "D", or Channel 23C is 26.965 MHz (CB Channel 23) and Sub-Band "C" or Channel 3A is 446.0125 MHz (CB channel 3).

As of 2007, the FCC authorized additional 40 channels from 446 to 460 MHz in a frequency range for use with radios designed as mobile two-way communication devices ("walkie-talkies"). The new frequencies are referred to as the sub-bands, B (446.025 - 446.05), C (446.075 - 446.125), D (446.075 - 446.175), and E (460).

All of these sub-bands have 20 channels each; which overlap with the Citizens Band Radio Service frequencies in some cases in that they begin at 5 kHz intervals like CB does (but end at 25 kHz intervals rather than 10 kHz as CB does).

The plan allocates 20 channels at 446.025 MHz, C Band (CB radio channel 3), 20 channels at 446.075 MHz, D Band (CB radio channel 6), and a total of 40 channels between 440.975 - 445.975 MHz and 451.975 - 458.975 MHz, E Band (460).

The sharing of frequencies with the amateur radio service is intentional; it was seen as a way to improve communication in areas where hams have an actual license requirement because the hams could use these channels on purpose without interference from citizens band users who would not use correct FCC legal operating procedures and reserved frequencies anyway ("AKA Pirate"). This has since been repealed as of 2011.

The FCC added ten channels at 446.0375 MHz in 1994, A Band (CB radio channel 12), for use with low power units ("baby boomers"). This band overlaps the 10-meter amateur radio service allocation (repeater outputs) between 440.275 - 445.275 MHz and 451.275 - 458.275 MHz, but no interference is expected from hams who will not transmit on these frequencies even if they have hf legal licenses because of their power limitations.

The 446/10 Meter repeater sub-band plan is a duplex pair within a single 26 channel frequency block that has been allocated to one user or another since 1982; the sharing is intentional as it was seen as a way to improve communication in areas where hams have an actual license requirement because the hams could use these channels on purpose without interference from citizens band users who would not use correct FCC legal operating procedures and reserved frequencies anyway ("AKA Pirate"). This has since been de-authorized in 2015.

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