Ever Wonder why Idaho license plates have a # followed by a letter at the beginning? Main Boise Real Estate

Simply put, the letter represents the first letter of the county's name and the number shows, numerically, the alphabetical order of the counties.

Let me spell it out so it makes more sense. There are 44 counties in the state of Idaho and two of them start with the letter 'A.' So 1A is Ada County and 2A is Adams County.

Idaho License Plate

source: Wikipedia

Here is the list of counties and their representing initials on an Idaho License plat.


  • 1A Ada (Boise)
  • 2A Adams (Council)
  • 1B Bannock (Pocatello)
  • 2B Bear Lake (Paris)
  • 3B Benewah (St. Maries)
  • 4B Bingham (Blackfoot)
  • 5B Blaine (Hailey)
  • 6B Boise (Idaho City)
  • 7B Bonner (Sandpoint)
  • 8B Bonneville (Idaho Falls)
  • 9B Boundary (Bonners Ferry)
  • 10B Butte (Arco)
  • 1C Camas (Fairfield)
  • 2C Canyon (Caldwell)
  • 3C Caribou (Soda Springs)
  • 4C Cassia (Burley)
  • 5C Clark (Dubois)
  • 6C Clearwater (Orofino)
  • 7C Custer (Challis)
  • E Elmore (Mountain Home)
  • 1F Franklin (Preston)
  • 2F Fremont (St. Anthony)
  • 1G Gem (Emmett)
  • 2G Gooding (Gooding)
  • I Idaho (Grangeville)
  • 1J Jefferson (Rigby)
  • 2J Jerome (Jerome)
  • K Kootenai (Coeur d’Alene)
  • 1L Latah (Moscow)
  • 2L Lemhi (Salmon)
  • 3L Lewis (Nez Perce)
  • 4L  Lincoln (Shoshone)
  • 1M Madison (Rexburg)
  • 2M Minidoka (Rupert)
  • N Nez Perce (Lewiston)
  • 1O Oneida (Malad City)
  • 2O  Owyhee (Murphy)
  • 1P Payette (Payette)
  • 2P Power (American Falls)
  • S Shoshone (Wallace)
  • 1T Teton (Driggs)
  • 2T Twin Falls (Twin Falls)
  • V Valley (Cascade/ McCall)
  • W Washington (Weiser)

Idaho has been doing it this way since 1945. Vehicles like cars, trucks, and vans must have plates on the front and back of the vehicle. Motorcycles, all-terrain vehicles (ATVs), and trailers only require a plate on the back. Your rear license plate must also have a registration sticker that shows the current registration year.

Idaho vehicle registration fees are annual for passenger vehicles vehicles 8,000 lbs. and under. Fees are also determined by the vehicle's age and your county of residence. Passenger vehicles: 1 to 2 years old: $69.

The word "Potato" first apeared on an Idaho license plate in 1928. The now famous words "Famous Potatoes" apeared on our plates in 1957.

History of Idaho License Plates

Each city government wase originally responsible for registering motor vehicles from 1909 through 1912.  The first Idaho license plates were made of porcelain, brass and steel. Idaho license plates were issued by the state begining in 1913. 

  • The first slogan on Idaho’s license plates appeared in 1928 where the word POTATO at the bottom of plate was stamped/ embossed, in addition to an image of a potato. 
  • The 1940 plate commemorated "50 YEARS OF STATEHOOD" at the top and "1890 IDAHO 1940" at the bottom. 
  • "SCENIC" was used on all Idaho license plates issued between 1941 through 1946. 
  • The 1947 Idaho license plate has "VACATION WONDERLAND" and the image of skiers embossed/stamped on it.
  • The 1948 Idaho license plate was embossed/ stamped with "WORLD FAMOUS POTATOES" at the bottom.  An image of a potato was placed between the county code and license plate number. 
  • Between 1953 AND 1956 the slogan was changed to "WORLD FAMOUS POTATO." 
  • Beginning in 1957, all Idaho license plates were issued with the slogan "FAMOUS POTATOES."

The 1928 potato Idaho license plate was the most popular issue in the United States.  The detail of the embossing/stamping including the de-bossed potato “eyes” was an engineering marvel back in 1928.  Idaho license plates for 1928, 1947 and 1948 are so rare that few are ever seen in public.

Idaho License Plate

Retro-reflective film license plates were introduced in Idaho in 1972, green on reflective white.  The state of Idaho has used retro-reflective film on its license plates continuously since 1972.  The 1948 and 1949 Idaho license plates show screened images of potatoes with a dab of butter.

 The 1985 Idaho license plate base is same as the 1983, but was modified to show snow-capped mountains.  Recently, as Idaho became a retirement destination for Californians, the restoration of antique cars emerged from a backyard garage hobby to a growing business. 

Posted by Joey at 1/4/2019 9:34:00 PM
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