| City: | Cincinnati, Ohio |
| Names to Avoid: | Internal Revenue Service |
| County: | Hamilton County |
| Timezone: | Eastern (GMT -05:00) |
| Local Time: | 9:57:29 PM |
| Population: | No Population Data |
| Area Codes: | 283 / 513 |
| Classification: | Unique [Company/Government] |
| Coordinates: | 39.1619, -84.4569 |
| Quick Link: |
The Internal Revenue Service operates under dedicated ZIP code 45999 in Hamilton County, Ohio. The IRS is the federal agency responsible for collecting taxes and administering the Internal Revenue Code. Cincinnati historically served as one of the IRS's major processing centers, though the Cincinnati Tax Processing Center closed by the end of 2019, with bulk processing shifted to Kansas City and Ogden.
Located in Cincinnati's Central Business District, this unique postal designation has served IRS correspondence for over two decades. The 8 delivery codes on file route mail to Department of the Treasury and IRS facilities on 4th Street. While bulk tax return processing moved elsewhere, Cincinnati addresses continue handling specialized IRS correspondence including tax-exempt entity matters and certain business filings. Cincinnati serves as the valid mailing city for this designation.
Buildings registered in the USPS ZIP+4 database with designated codes for direct mail delivery.
ZIP Code 45999 is assigned to a single organization or institution. Detailed business demographics are not published for unique ZIP Codes.
| # Residential Mailboxes: | 0Source: USPS |
| # Business Mailboxes: | 0Source: USPS |
| Total Delivery Receptacles: | 0Source: USPS |
| Single Family Delivery Units: | 0Source: USPS |
| Multi Family Delivery Units: | 0Source: USPS |
| # of Businesses: | 0Source: CBP |
| 1st Quarter Payroll: | $0Source: CBP |
| Annual Payroll: | $0Source: CBP |
| # of Employees: | 0Source: CBP |
ZIP Code 45999 is located in Hamilton County, Ohio, within the Cincinnati, OH-KY-IN Metropolitan Statistical Area (CBSA 17140) and Ohio's 4th Congressional District. This Metro area has a population of 2,130,151 people, about 0.00% of whom live in ZIP Code 45999. It covers 0 sq mi of land and a water area of 0 sq mi.
| CBSA Name: | Cincinnati, OH-KY-INSource: Census |
| CBSA Number: | 17140Source: Census |
| CBSA Type: | MetroSource: Census |
| CBSA Division: | --Source: Census |
| CBSA Population: | 2,130,151Source: Census |
| MSA: | Cincinnati-Hamilton, OH-KY-IN CMSASource: Census |
| Land Area: | --Source: Census |
| Water Area: | --Source: Census |
| Congressional District: | 04Source: USPS |
| Congressional Land Area: | 4382.19 sq miSource: Census |
| PMSA: | Cincinnati, OH-KY-IN PMSASource: Census |
| Intro Date: | < 2004-10Source: ZIP-Codes.com |
| Place FIPS Code: | 3915000Source: Census |
| Place Name: | Cincinnati city; OhioSource: Census |
We could not locate which school district 45999 belongs to, but we will update this once new district data is released. There are no public schools nor private schools with a mailing address in this ZIP Code. Listing Nearby schools instead. It also has 6 colleges, universities or post secondary education institutions nearby which would be a short commute to.
Our sources include trusted federal and licensed data from the United States Postal Service, U.S. Census Bureau, U.S. Geological Survey, Centers for Medicare & Medicaid Services, and the National Center for Education Statistics, along with proprietary datasets created by ZIP-Codes.com. Data last updated on February 1, 2026.