Using Commas in Numbers, Addresses, and Letters

Using Commas in Numbers, Addresses, and Letters.

By Grant Savage

Using Commas in Numbers

Use a comma or commas to separate groups of three digits in large numbers.

Commas make large numbers easier to read by grouping the digits. In general, with large numbers of more than three digits, use a comma after every third digit starting from the right. However, do not use commas in ZIP codes, telephone numbers, page numbers, years, serial numbers, or hours numbers.

​Comma Rule	​Example
​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 [phone] Serial number 777095822 Page 1005 2399 Berkeley Place

Using Commas with Addresses and Letters.

Using Commas with Addresses and Letters

Use commas to punctuate specific parts of addresses and letters.

Commas are used in addresses, salutations of friendly letters, and closings of friendly or business letters.

​Comma Rule	​Example
​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,