What Is the Abbreviation for Ohio?
The standard abbreviation for Ohio is OH. This page explains why Ohio uses OH, 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.
What Is the Abbreviation for Ohio?
OH is the standard abbreviation for Ohio. OH is the form used in mailing addresses, forms, databases, and current style guides.
Use OH for Ohio in mailing addresses, shipping labels, official forms, and database records.
Why Ohio Uses OH
Ohio's USPS abbreviation is OH.
OH has been Ohio's standard postal abbreviation since 1963 and is the form used in current addresses, forms, and databases.
Old Abbreviation for Ohio
Before the USPS two-letter system became the mailing standard in 1963, printed reference books and newspapers often used longer abbreviations with punctuation. For Ohio, that older style was usually Ohio.
That older form still appears in historical texts, archival material, and some legacy style guides, but the modern postal and database standard is OH. If someone searches for old abbreviation for Ohio, the practical answer is to recognize Ohio and use OH in current writing and addresses.
How to Write Ohio 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.
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.
OH Compared With Similar State Codes
OH is clear in an address, but outside that context it can look like ordinary text, so people sometimes double-check it.
Related Abbreviation Questions
These states share a first letter, region, or alphabetical position with Ohio and are commonly checked alongside it.
Capital, Region, and Context
Ohio belongs to the Midwest region. Its capital is Columbus, and its postal code OH is used in addresses, forms, and databases throughout the country.
Ohio entered the Union on March 1, 1803.
FAQ
What is the abbreviation for Ohio?
The standard USPS abbreviation for Ohio is OH.
What is the postal abbreviation for Ohio?
OH is the two-letter postal abbreviation for Ohio. It is the form used in mailing addresses, shipping labels, forms, and databases.
How do you abbreviate Ohio?
Abbreviate Ohio as OH in current USPS, mailing, and database use.
Why is Ohio abbreviated OH?
Ohio's USPS abbreviation is OH.
What does OH stand for?
OH stands for Ohio in the USPS state abbreviation system.
What is the old abbreviation for Ohio?
Older editorial styles often wrote Ohio as Ohio. For mailing and database use, the modern standard is OH.
How do you write a Ohio mailing address?
Use the city name, then the two-letter postal code OH, then the ZIP Code. For example: Columbus, OH 00000.
What state is OH?
OH is the postal abbreviation for Ohio, located in the Midwest region. The capital is Columbus.
Test All 50 State Abbreviations
Now that you know OH stands for Ohio, see how many of the other 49 you can get right. The M-states and I-states trip up most people.