noun

ZIP code

ZIP kohd

ZIP code (noun) means a postal code used in the United States, consisting of five digits, sometimes followed by a hyphen and four more digits that pinpoint a smaller delivery area. Example: “Enter your ZIP code to see delivery options.”

noun

A postal code used in the United States, consisting of five digits, sometimes followed by a hyphen and four more digits that pinpoint a smaller delivery area.

"Enter your ZIP code to see delivery options."

"The full ZIP code on the invoice was 90210-4817."

informal A rough shorthand for the neighbourhood or area a person lives in, and by extension its wealth or character.

"Life expectancy in this country still depends heavily on your ZIP code."

"Two schools, three miles apart, different ZIP codes, completely different funding."

How to use ZIP code

Learner’s notes

In plain EnglishThe number that says which part of the US an address is in.

When to use it

Standard American English. Officially styled ZIP in capitals, though lower-case "zip code" is very common in ordinary writing.

Memory tip

Use ZIP code only for United States addresses. The United Kingdom has postcodes, Canada has postal codes, and each has a different format.

Trace the full origin ↓

Easily confused with

ZIP code vs postcode ZIP code vs area code ZIP code vs postal code

Common pairings

enter your ZIP code ZIP code lookup ZIP+4 by ZIP code

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Fill the gap

Can you complete this real example?

Enter your _____ to see delivery options.

Etymology

ZIP is an acronym for Zone Improvement Plan, the United States Post Office system introduced in 1963; the capitalisation reflects the acronym.

Origin: English

Rhymes for ZIP code

ode rode code mode bode node lode abode erode Rhode Goode encode

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Frequently asked questions

What is the difference between a ZIP code and a postcode?

They do the same job in different countries. ZIP code is the American term and is five digits, optionally extended to nine. Postcode is the British and Australian term; UK postcodes mix letters and numbers, such as SW1A 1AA, and identify a much smaller area than a US ZIP code does.

What does ZIP stand for in ZIP code?

Zone Improvement Plan, the sorting system the United States Post Office introduced in 1963 to speed up mail routing. That is why it is properly written in capitals.

What is the difference between a ZIP code and an area code?

A ZIP code identifies a postal delivery area for mail. An area code is the three-digit prefix on a US telephone number identifying a telephone region. They cover different territories and are never interchangeable.

What are the extra four digits in a ZIP+4?

They narrow the address down further, typically to a specific block, building or group of post office boxes. They are optional for senders but help mail get sorted and delivered more quickly.