Kentucky Abbreviation: KY and Ky.

The abbreviation for Kentucky at a glance

A quick test helps. If a mail carrier, a scanner or a database will read it, use KY. If a person will read it inside a paragraph, spell out the name, and save Ky. for places where space is short.

KY on envelopes, forms and labels

The two-letter postal codes came into use in the 1960s, when ZIP codes arrived and mail sorting needed short, uniform state codes. The Postal Service asks for the code in capitals with no punctuation, with the ZIP code right behind it.

Dropdown menus on websites, driver records and tax forms all use KY as well. If a form gives you a box for two letters, KY is the only correct answer for Kentucky.

What is the abbreviation for Kentucky in AP style?

News writers following AP style write the state name in full inside a story. Where space forces a shorter form, say in a dateline, a photo caption, a list or a table, AP uses Ky., not the postal code.

Older style guides and many legal and academic citations use the same Ky. form. You may also see it in historical documents, church records and old maps. It is a true abbreviation, a shortened word, rather than a code built for machines.

Do not mix up KY with KS or other codes

Kentucky and Kansas both start with K, and a tired eye can trade one code for the other. A package sent to the wrong one can travel hundreds of miles before anyone notices.

• KY is Kentucky. The traditional form is Ky.
• KS is Kansas. The traditional form is Kan. or Kans.
• KT and KN are not state codes at all, even though people sometimes guess them.
• TN is Tennessee, Kentucky's neighbor to the south, and a common mix up on regional forms.

For the whole set of fifty codes, see the state abbreviations list. The Kansas abbreviation page covers the other K state in detail.

A few facts about the Bluegrass State

Kentucky joined the Union in 1792 as the 15th state. Its capital is Frankfort, and its largest city is Louisville. Officially it is the Commonwealth of Kentucky, one of four states that call themselves a commonwealth, along with Massachusetts, Pennsylvania and Virginia. None of that changes the code. Even official state mail uses KY.

The nickname, the Bluegrass State, comes from the grass that grows in the central part of the state. You will sometimes see KY used as a casual shorthand on shirts, bumper stickers and sports banners, where it simply stands for the state as a whole.

Tips for writing the Kentucky abbreviation

1. Write KY in capitals. A lowercase ky or a mixed Ky on an envelope looks like a typo.
2. Never add periods to the postal code. K.Y. is wrong in every style.
3. Put a comma between the city and the state in a sentence, and another after the state: "She works in Louisville, Ky., near the river."
4. Spell out Kentucky when it stands alone, as in "Kentucky has many caves."
5. Use the same form throughout one document so readers are not left guessing.

Wondering how a postal code differs from an abbreviation? See acronym vs abbreviation explains the terms.