Idaho Abbreviation: ID

Idaho abbreviation options at a glance

For almost every task you only need two choices: ID for addresses and boxes, Idaho for everything a person reads as a sentence.

How to write the ID state abbreviation on an address

The code follows the city name and a comma; next comes one space and the ZIP code. Keep both letters capitalized.

Some quick checks before you mail:

• Idaho ZIP codes begin with 832 through 838. A ZIP that starts with 5 likely belongs to Iowa or another Midwest state.
• Do not write "Id." or "I.D." in the state spot. Sorting machines look for the plain code.
• On a drop down menu, choose Idaho by name and the form will save ID for you.

All fifty pairs of letters are listed in our state abbreviations guide.

Why news style spells out Idaho

AP style, the guide used by most US newsrooms, writes state names in full inside news articles. For a handful of short names it goes further and never abbreviates them at all, not even in datelines. Idaho is on that list, along with Alaska, Hawaii, Iowa, Maine, Ohio, Texas and Utah.

So a report starts "BOISE, Idaho" rather than using a short form. Students and office writers can borrow the habit: write Idaho in sentences and save ID for the address block.

ID can mean Idaho or identification

The letters ID do double duty, which can cause a moment of confusion on a form.

• Beside a city name and a ZIP, ID is the state: "Pocatello, ID 83201."
• On a sign or a form field, ID usually means identification: "Bring a photo ID."
• In a sentence like "Idaho ID required," both appear, meaning an identification card issued by the state of Idaho.

Other state codes that start with I are easy to swap by mistake:

• IA is Iowa.
• IL is Illinois.
• IN is Indiana.

A simple way to remember: ID uses the first two letters of Idaho.

Sentences that use the Idaho abbreviation

• "Send the invoice to Coeur d'Alene, ID 83814."
• "State of residence: ID" on a college application.
• "We drove through Idaho on the way to the park."
• "The team from Moscow, Idaho, won the regional title."
• In a shipping spreadsheet, the state column reads ID for every Idaho order.

If the state name comes after a city partway through a sentence, it gets commas before and after, as in the fourth example.

Idaho background that helps with the code

Idaho became the 43rd state in 1890. Boise serves as both the capital and the biggest city. People call Idaho the Gem State. It borders six states, including Montana (MT), Washington (WA), Oregon (OR), Utah (UT), Nevada (NV) and Wyoming (WY), and it touches Canada to the north.

Like the other state codes, ID came from the Postal Service in the 1960s, when ZIP codes were introduced and states needed short codes of a fixed length.