U.S. State Abbreviations: Map and All 50 State Postal Codes

Quick Answer

The United States has 50 state abbreviations, each a USPS-assigned two-letter postal code written in uppercase with no periods. These codes are separate from traditional abbreviations and from codes assigned to the District of Columbia and U.S. territories.

U.S. State Abbreviations at a Glance

Here is the complete list of the 50 states, their capitals, and their USPS postal abbreviations.

What Are U.S. State Abbreviations?

U.S. state abbreviations are standardized two-letter postal codes used to identify states in mailing addresses and many other systems. USPS lists the state codes as two uppercase letters without periods.

For example, California is CA, Florida is FL, Massachusetts is MA, and Washington is WA.

USPS Abbreviations vs. Traditional State Abbreviations

The two-letter codes above are postal abbreviations. They should not be confused with older traditional abbreviations such as “Calif.” for California or “Mass.” for Massachusetts.

The modern two-letter system was introduced in 1963 as part of the national rollout of five-digit ZIP Codes. USPS explains that shorter state codes helped leave enough room for the ZIP Code on the last line of a mailing address. In 1969, USPS changed Nebraska’s code from NB to NE to avoid confusion with New Brunswick, Canada.

Why Do U.S. States Have Two-Letter Postal Codes?

The codes provide a consistent, compact way to identify states in addresses. USPS says the two-letter abbreviations make it possible to fit the city, state and ZIP Code within the available address-line space.

They are also commonly used in forms, databases, maps and other records where a short state identifier is useful.

District of Columbia and U.S. Territories

The 50 state abbreviations are separate from codes used for the District of Columbia and U.S. possessions. USPS’s current list includes DC for the District of Columbia, PR for Puerto Rico, GU for Guam, AS for American Samoa, MP for the Northern Mariana Islands, and VI for the U.S. Virgin Islands.

These places should not be counted as additional U.S. states. The United States consists of 50 states and the District of Columbia; U.S. territories are a separate category.

How to Use a U.S. State Abbreviation

When you are entering a U.S. address, use the standardized two-letter USPS code when the form or addressing standard calls for it. For example:

• New York, NY
• California, CA
• Texas, TX
• Florida, FL

For official mailing-address standards, refer to the current USPS list rather than relying on older abbreviations.

Planning a Trip to the United States?

If you are using state abbreviations while planning a U.S. trip, you may also need to organize your travel dates, destinations and medical coverage before departure. OnshoreKare offers visitor insurance options for people travelling to the United States.

Explore U.S. visitor insurance options.

Official Sources and References

• USPS Postal Explorer: Two-Letter State and Possession Abbreviations
• USPS: History of State Abbreviations
• U.S. Census Bureau: United States Profile