What is my ZIP code?

ZIP stands for Zone Improvement Plan. The U.S. Postal Service introduced ZIP codes on July 1, 1963, to make mail sorting faster. A ZIP code is a number for a mail delivery route or group of post office boxes, not a legal boundary. The first digit covers a group of states, from 0 in the Northeast to 9 in the West. The city name in a mailing address is the post office name and can differ from your town or city.

The ZIP+4 adds four digits after a space or dash. USPS introduced it in 1983. The extra digits narrow delivery to a block face, a large building, or a group of PO boxes. To find yours, use the official USPS ZIP Code Lookup by address. It shows the ZIP+4 for most addresses. You do not usually need the +4 for a form.

Enter the billing ZIP code. That is the ZIP the card issuer has on file for the account. It is usually the ZIP of the home address you used when you opened the card, not the ZIP where you are right now. If you have moved, update your billing address with the bank first. Guessing or entering a random ZIP can make the payment fail. For the exact ZIP on file, call the number on the back of your card.

Enter the ZIP you registered with the card when you activated it online or by phone. If you never registered a ZIP, the card issuer may not have one. In that case, check with the issuer using the number on the back of the card. Do not enter the ZIP of the store where you bought the card. Prepaid card rules vary by issuer, so the safest step is to ask them.

ZIP codes are mail routes, not areas. A single place can sit near a boundary between two routes. Your device location may fall in one ZIP, while the address on your mail is delivered by a different route. Some ZIPs are for PO boxes only, so they have no street area at all. The Census Bureau makes approximate areas for statistics, but they do not always match USPS delivery routes. Trust your mailing address for forms.

The city name in a mailing address is the name of the USPS post office that serves it, not your local government. A home in a suburb or an unincorporated area often uses the name of a nearby city, and one ZIP code can cover parts of several towns. That is normal and does not mean your address is wrong. For forms, use the city the post office uses, as shown by the USPS lookup.

Yes, in everyday use. The USPS calls its system ZIP code. Other countries call their national systems postal codes. They do the same job: route mail to a specific delivery area. If a website or form asks for a postal code and you are in the United States, enter your ZIP code. The format may differ, but the concept is the same.

The first digit is a group of states, running roughly from 0 in the Northeast to 9 in the West. The second and third digits narrow the region to a sectional center or a large city. The fourth and fifth digits identify a post office or delivery area within that region. ZIP+4 adds four more digits for a block face, building, or PO box group. It is a mail routing number, not a map area.