Avalara > Blog > Developer > Take a REST for sales tax: Easy and free tax rates for developers

Take a REST for sales tax: Easy and free tax rates for developers

  • Jan 13, 2015 | Lokeuei

Tax compliance is challenging, and static tax rate tables are a common place to start looking for answers. Manually updating tax rates from a file is inefficient, though, and tax rates may change at any time – not just once per month. This is the perfect use case for a REST API, so that’s what we built. Our new Tax Rates API makes it easy to get the most current and accurate tax rate in your software. And it’s completely free.


After signing-up for a free API key, our REST API design makes it easy to start retrieving rates in just a few minutes. Integration in your project should be quick and easy. Get started by reading our API documentation.


Five Digit Zip Codes: If you just want to retrieve or update the tax rate for a zip code, we’ve got you covered.

Street Addresses: Most free tax rate look-up tools only tell you the rate for a ZIP code. But in some cases, tax rates for a location will vary down to the specific street address level. This is because ZIP codes don’t align with taxing jurisdictions. In fact, a single ZIP code can have up to 20 different tax rates.


For those that use Zapier, we’ve added integrations with Google Contacts and Outlook.com that automatically updates the tax rate for all of your contacts.

Users can retrieve tax rates for US zip codes and street addresses, and we’ll consider adding data for other countries based on user feedback.

We would love to see Tax Rates API data being used for research, in mobile apps and consumer software, as well as business-centered software. Please let us know about your interesting use on Twitter @avadev.


Other companies charge for their tax rates API - don’t be fooled. We don’t charge for this data. Period.

After all, the primary reason tax rates often don’t tell the whole story for more complicated tax calculations. Applicable rules not only take into account the location of the sale, but also the item or service purchased. For example, in New York City burritos are taxable but tacos are not. For these situations, tax rates are just too simple a model. Relying on a rate based on ZIP alone can create substantial audit exposure for your business.

We’ve made tax rates available for free, but if you need a more robust tax solution and are interested in AvaTax you can get started with a free trial of our SDK.

For information and to sign up for this free service, please visit our website:


Sales tax rates, rules, and regulations change frequently. Although we hope you'll find this information helpful, this blog is for informational purposes only and does not provide legal or tax advice.
Avalara Author
Avalara Author Lokeuei