The Finder REST Web Service

Overview

Our web services allow software developers to connect their applications to Ohio sales tax rate information over the internet. In addition to using The Finder web site, businesses can use these services to add real-time Ohio tax rate lookups to their own software. Developers who use these services should have experience building web-based applications and services.

The current REST API supports tax-rate lookups by address, zip code, and coordinates. For legacy users looking for information on the SOAP-based service, please refer to the SOAP Web Service section here.

Base path: /finder/api/v1

Authentication and Headers

x-api-key is required for these API routes.
x-globaltransaction-id is optional for all operations. If omitted, the service generates one.
x-source is optional and used for request tracking.

Current Operations

Operation	Contract	Method and Path	Behavior
GetTaxRatesByAddress	Address contract	POST /tax-rates/address	Returns sales, school district, and municipal tax data for the address, or an error response when no tax rates are found.
GetTaxRatesByZipCode	Zip Code contract	POST /tax-rates/zipcode	Returns sales, school district, and municipal tax data for zip code, or an error response when no tax rates are found.
GetTaxRatesByCoordinates	Coordinates contract	POST /tax-rates/coordinates	Returns sales, school district, and municipal tax data for latitude/longitude coordinates, or an error response when no tax rates are found.

Request Payload Highlights

All three operations require a date field formatted as MM/DD/YYYY.
taxableAmount is optional for all operations and defaults to 0.
taxTypes is optional for all operations. If omitted or empty, all tax types are returned.

Sample cURL (Address)

curl --request POST "https://thefinder.tax.ohio.gov/finder/api/v1/tax-rates/address" \
  --header "Content-Type: application/json" \
  --header "x-api-key: YOUR_API_KEY" \
  --header "x-source: your-system" \
  --data '{
    "inputAddress": {
      "streetAddress": "4485 Northland Ridge Blvd",
      "city": "Columbus",
      "state": "OH",
      "zipCode": "43229"
    },
    "date": "08/13/2026",
    "taxableAmount": 100
  }'

Status Codes

200: Returned when processing is successful. The response body contains either the tax rate data or a message in cases where no tax rates are found.
400: Validation or malformed request payload.
401: Missing or invalid x-api-key.
403: Blocked by CORS policy.
429: Rate limit exceeded.
500/502/504: Internal, upstream, or timeout errors.

Support

The Finder web service is available 24 hours a day, 7 days a week, except during scheduled maintenance. Technical support is available Monday through Friday from 8 a.m. to 5 p.m. Eastern Time.

The Ohio Department of Taxation can help with general questions about the web service and high-level implementation issues. However, we do not provide support for building or developing web services. Developers should have experience working with web services before using this service.

For technical questions or questions regarding the registration process, please e-mail the Department of Taxation at TheFinderHelp@tax.ohio.gov.

By providing this information, neither the State of Ohio nor the Ohio Department of Taxation assumes any liability for any errors or omissions in the data provided by this system, or in any other respect.

For sales and use tax purposes, in conformity with the Streamlined Sales Tax Agreement and the Mobile Telecommunications Sourcing Act, vendors and sellers may rely on this information for use in finding the rate of a location for the collection of sales or use tax based on the date used for the search. By providing this information, neither the State of Ohio nor the Ohio Department of Taxation assumes any liability for any errors or omissions, or in any other respect. The information provided is not intended to be used to determine the taxability of an individual transaction. For questions on taxability, please refer to tax.ohio.gov or to the Ohio Revised Code.

If a school district income tax filing error occurs because of incorrect information provided by this system, the Department of Taxation will consider waiving the penalty imposed based on school district income tax liability. However, the Ohio Department of Taxation cannot waive additional tax or interest that results from such errors and penalties imposed by a municipality must be resolved with the appropriate taxing authority.

After receiving tax jurisdiction information for your address in The Finder, the Ohio Department of Taxation recommends verifying this information with the appropriate municipality or county auditor even if no tax liability is indicated. If you feel there is an error or have questions regarding the information you have received, please e-mail the Department of Taxation at TheFinderHelp@tax.ohio.gov .