Alaska has the U.S. state abbreviation that comes first alphabetically: AK. The comparison is between the official two-letter postal abbreviations, not the full state names.
The United States Postal Service introduced the familiar two-letter state codes in 1963 to make addressing more efficient. Alaska’s code is AK, formed from the first and an identifying letter of its name. When the codes are sorted alphabetically, AK comes before Alabama’s AL, Arkansas’s AR, Arizona’s AZ, and every other state code.
This question can cause confusion because Alaska does not come first when state names are alphabetized—Alabama does. The answer depends specifically on comparing abbreviations. Alaska also has a distinctive code because “AL” is reserved for Alabama, while “AK” avoids confusion with the other states beginning with A.