IA is the two-letter written short form of Iowa, a state in the middle of the United States. American post and almost every form uses two letters for each state; Iowa’s pair is IA. You will see it on envelopes, IDs, sports tables, and news: Des Moines, IA. You do not say “I-A” in place of the name; when you speak, you still say Iowa. Other groups also use IA for their own names, but this entry is only the state. Though actually, the letters are easy to guess wrong: Iowa does not get IO.

愛荷華州（Iowa）的郵政縮寫。台灣稱愛荷華；中國大陸常寫艾奥瓦。