The Tax990 API Brings IRS-Authorized 990-N E-Filing to Your Platform

Estimated reading time: 10 minute(s)

If your platform serves nonprofits, you already know the pattern. Organizations use your software to track donations, manage grants, and handle their books, and then they leave to file their annual return somewhere else. That handoff is where the experience breaks.

The Tax990 API closes that gap. It’s a REST API that lets fintech platforms, nonprofit accounting tools, donor management systems, and grant management platforms embed IRS-authorized 990-N e-filing right inside their own products. It’s available now, and support for additional 990 series forms is planned for future releases.

Why Start With Form 990-N

Form 990-N, also called the e-Postcard, is the return that small nonprofits with gross receipts of $50,000 or less file each year. That’s a huge and underserved slice of the nonprofit world, and it’s the group most likely to be filing on their own with no software support at all.

“Nonprofit organizations rely on the software platforms they use every day to help them manage their finances, track donations, and report on their work,” said Naga Palanisamy, President of SPAN Enterprises. “Until now, most of those platforms have stopped short of handling 990 compliance, leaving nonprofits to navigate a separate filing process on their own. Launching with Form 990-N lets us bring this capability to the platforms that serve the smallest and most resource-constrained nonprofits first, with a clear path to broader form coverage as we build.”

Starting with 990-N means you can serve your smallest customers first, without building or maintaining IRS infrastructure yourself.

What the API Handles for You

The current release covers the full 990-N filing process, not just form submission. It includes a real-time IRS business rules validation engine that catches field-level errors before anything goes to the IRS, so filers fix problems up front instead of waiting on a rejection.

It also handles automated rejection parsing and retransmission support, plus status tracking all the way through IRS acknowledgment. You get a complete picture of where every filing stands.

Key API Capabilities

Here’s what you get out of the box:

• Free Sandbox — A sandbox environment that mirrors production exactly, so your developers can test the complete filing workflow, including simulated IRS responses, before going live.
• SDKs in multiple languages — Official SDK libraries cover the full 990-N filing process, which speeds up integration across the stacks your team already uses.
• Webhooks — Real-time event notifications land in your application as IRS status updates happen, so you never have to poll for changes.
• Flexible integration models — Two ways to connect, depending on how much of the filing experience you want to own.

Two Ways to Integrate

The Public API lets your platform call Tax990 endpoints directly and keep the entire filing experience inside your own interface. Your users never leave your product.

The API for Platforms model lets your clients transfer their existing data to Tax990 in a few clicks and finish filing within the Tax990 application. It’s the faster path if you’d rather not build out the full filing UI yourself.

Built for Compliance and Security

Tax990 has operated as an IRS-authorized e-file provider for more than 10 years and holds a SOC 2 Type II certification. The API maintains 99.9 percent uptime and uses TLS 1.3 encryption in transit and AES-256 encryption at rest. Audit logs for every submission, status change, and IRS acknowledgment are retained for seven years.

That means when you build on the API, the compliance and security work is already handled.

Start Building Today

You can explore the docs, spin up a free sandbox, and test the full filing workflow right now.

Get Started With the Tax990 API

Software platforms interested in the API for Platforms integration model can reach the partnerships team at [email protected].