GMRS

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General Mobile Radio Service

GMRS (and by extension, FRS) evolved out of the original 465 MHz "Class A" CB service. Calling frequency 462.675 MHz CTCSS 141.3 Hz (sometimes referred to as the "travel channel"). See page for FRS for information about combined FRS/GMRS "bubble pack" radios. As of late 2017, the FCC legalized the 8 "GMRS only" 462 MHz frequencies as part of the FRS service, changing the number of shared frequencies from 7 to 15 and legalizing the use of all 22 channels for simplex use under the FRS rules. GMRS license holders are still granted higher transmit power privileges and use of repeaters under the new rules.

Maximum power 50 watts on GMRS is except on shared narrow band channels (FRS channels 1-7) where maximum power is 5 watts. Wide band FM (25 kHz or 20K0F3E, 16K0F3E or similar) or narrow band FM (11K2F3E, 11K0F3E and several other emissions with even narrower bandwidths) allowed on the 16 GMRS only frequencies for repeater or simplex use. Low power mobile and portable radios generally use narrow FM for compatibility with other handheld FRS radios aimed at the consumer market.

Like the FRS service, the FCC permits use of digital transmissions on the GMRS service. Digital transmissions are limited to text messages, requests for text messages, group chat messages, in-range location "ping" transmissions to verify that a radio is still within range of another radio (automatic range transponder capability), GPS location transmissions, GPS location requests, etc.

GMRS Frequencies GMRS Channels

  • Channel 01 - 462.5625 MHz - 5 watt power limit, simplex only
  • Channel 02 - 462.5875 MHz - 5 watt power limit, simplex only
  • Channel 03 - 462.6125 MHz - 5 watt power limit, simplex only
  • Channel 04 - 462.6375 MHz - 5 watt power limit, simplex only
  • Channel 05 - 462.6625 MHz - 5 watt power limit, simplex only
  • Channel 06 - 462.6875 MHz - 5 watt power limit, simplex only
  • Channel 07 - 462.7125 MHz - 5 watt power limit, simplex only
  • Channel 08 - 467.5625 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 09 - 467.5875 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 10 - 467.6125 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 11 - 467.6375 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 12 - 467.6625 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 13 - 467.6875 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 14 - 467.7125 MHz - 0.5 watt power limit, unlicensed FRS simplex
  • Channel 15 - 462.5500 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 16 - 462.5750 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 17 - 462.6000 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 18 - 462.6250 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 19 - 462.6500 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 20 - 462.6750 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 21 - 462.7000 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex
  • Channel 22 - 462.7250 MHz - 50 watt power limit, simplex or repeater output, shared with FRS simplex

Channels 1-22 are shared with the FRS service. FRS users may operate simplex only.

Channels 8-14 are simplex only and limited to 0.5 watt power output. GMRS users may transmit up to 5 watts on 462.5625 MHz, 462.5875 MHz, 462.6125 MHz, 462.6375 MHz, 462.6625 MHz, 462.6875 MHz and 462.7125 MHz (channels 1-7).

Licensed GMRS users and unlicensed FRS users are limited to 0.5 watts on 467.5625 MHz, 467.5875 MHz, 467.6125 MHz, 467.6375 MHz, 467.6625 MHz, 467.6875 MHz and 467.7125 MHz (channels 8-14).

Licensed GMRS users may transmit up to 50 watts on 462.550 MHz, 462.575 MHz, 462.600 MHz, 462.625 MHz, 462.650 MHz, 462.675 MHz, 462.700 MHz and 462.725 MHz (channels 15-22). GMRS users may use these frequencies for simplex (non-repeater) use or as repeater output frequencies. Because of the extensive simplex FRS use of all 22 channels, GMRS users are strongly encouraged to use CTCSS or DCS on any repeater pair and for simplex operations.

GMRS Repeaters

Ch Output MHz Input MHz
15 462.550 467.550
16 462.575 467.575
17 462.600 467.600
18 462.625 467.625
19 462.650 467.650
20 462.675 467.675
21 462.700 467.700
22 462.725 467.725


Many GMRS users refer to the wide band GMRS frequencies by the three digits after the frequency in MHz notation:

  • GMRS 550 - 462.5500 MHz
  • GMRS 575 - 462.5750 MHz
  • GMRS 600 - 462.6000 MHz
  • GMRS 625 - 462.6250 MHz
  • GMRS 650 - 462.6500 MHz
  • GMRS 675 - 462.6750 MHz
  • GMRS 700 - 462.7000 MHz
  • GMRS 725 - 462.7250 MHz

Resources and Further Reading:

List of Grandfathered GMRS Users Licenses - Grandfathered GMRS Entities by Zip Code

MyGMRS.com GMRS user resource

MyGMRS.com GMRS repeater listing - GMRS repeaters nationwide

ArtSci Publications - nationwide amateur and GMRS repeater listing



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