Postal Code Guide

What Is the Abbreviation for Wisconsin?

The standard abbreviation for Wisconsin is WI. This page explains why Wisconsin uses WI, how the code fits into the modern USPS system, what older printed abbreviations looked like, and which nearby or similar state codes people commonly confuse with it.

Postal Code

Traditional Form

Wis.

Capital

Madison

Region

Midwest

WI Wisconsin's modern two-letter state abbreviation.

What Is the Abbreviation for Wisconsin?

Wisconsin is abbreviated WI. Older sources may use Wis., but the two-letter postal form WI is the modern standard for addresses, forms, databases, and current style guides.

Use WI for Wisconsin in mailing addresses, shipping labels, official forms, and database records.

Why Wisconsin Uses WI

Wisconsin's USPS abbreviation is WI.

WI has been Wisconsin's standard postal abbreviation since 1963. The older form Wis. still appears in older sources, but WI is the form used in current addresses and forms.

All 50 abbreviations Wisconsin state page

Old Abbreviation for Wisconsin

Before the USPS two-letter system became the mailing standard in 1963, printed reference books and newspapers often used longer abbreviations with punctuation. For Wisconsin, that older style was usually Wis..

That older form still appears in historical texts, archival material, and some legacy style guides, but the modern postal and database standard is WI. If someone searches for old abbreviation for Wisconsin, the practical answer is to recognize Wis. and use WI in current writing and addresses.

How to Write Wisconsin in an Address

In standard American addressing, the state line uses the city name followed by the two-letter code and ZIP Code. The abbreviation stays uppercase and does not take periods.

Madison, WI 00000

That same format applies in checkout forms, school worksheets, CRM exports, spreadsheets, shipping labels, and government databases — anywhere a two-letter state code is required.

WI Compared With Similar State Codes

WI is commonly checked against WA, WV, and WY because the W-state abbreviations can look alike in short lists.

Washington (WA) Washington uses WA, while Wisconsin uses WI. West Virginia (WV) West Virginia uses WV, while Wisconsin uses WI. Wyoming (WY) Wyoming uses WY, while Wisconsin uses WI.

Capital, Region, and Context

Wisconsin belongs to the Midwest region. Its capital is Madison, and its postal code WI is used in addresses, forms, and databases throughout the country.