Using Commas in Numbers, Addresses, and Letters

​Use commas in large numbers of more than three digits.

​1,435 graduates
10,877 songs
1,909,498 voters

​Do not use commas in ZIP codes, telephone numbers, page numbers, years, serial numbers, or house numbers.

​ZIP code 28462 Year 2016
(303) 757-8822 Serial number 777095822
Page 1005 2399 Berkeley Place

​On an envelope or at the top of a letter, use a comma between the city and the state's postal abbreviation. (When applicable, also use a comma between the street address and the apartment number.)

​Mrs. Christine Becker
33 Henley Road, Apt. 103
Austin, TX 73344

​In a sentence, use a comma after each element of the address, other than the state's postal abbreviation.

​Send a thank-you note to Mrs. Christine Becker, 33 Henley Road, Apt. 103, Austin, TX 73344.

​Use a comma after the salutation in a friendly letter and after the closing in all letters.

​Dear Mike,
Dear Aunt Crystal,
Yours truly,
Sincerely,