SentiLink’s TCVS API: Instantly Verify U.S. Treasury Checks at Scale

In February 2025, SentiLink launched its Treasury Check Verification Service (TCVS) – a web-based tool that allows financial institutions to quickly verify U.S. Treasury checks. The service used the latest version of the Treasury's API, which supported validation of payee name in addition to other check metadata – a key field to verify in the fight against check washing and cooking. Since launch, over 100,000 checks have been verified, with 600 weekly active users across more than 50 financial institutions.

Today, we’re excited to introduce the next evolution: programmatic access to TCVS via API, a critical upgrade that will help institutions scale protection against counterfeit and altered checks. And just like the web version, SentiLink is providing API access for free so that stronger treasury check validation is more accessible to financial institutions across the country.

Why we built the API

From the moment we launched the web version, one request stood out: "Can you share API access?" Our partners needed more than a manual lookup interface. They needed the scale, speed, and automation of an API to stop fraudulent checks while quickly approving funds for legitimate consumers.

These partners were all stuck in various stages of the Treasury’s own complex process for provisioning API access, so we acted quickly to simplify the experience and enable broad adoption by creating SentiLink’s TCVS API: a REST API designed for real-time, high-volume treasury check verification.

SentiLink’s TCVS API provides:

• Real-time, programmatic validation of U.S. Treasury checks
• Payee name validation
• Simple integration using our RESTful endpoint
• No PII storage to ensure a secure, privacy-conscious implementation
  

How it works

To verify a check, you provide four required fields (and an optional fifth one, if you're verifying payee name):

• symbol_number (4 digits)
• serial_number (8 digits)
• amount (float)
• bank_rtn (routing number)
• payee (optional, but enhances fraud detection)

Example request:

In response the API returns the status of the check and whether the payee name, amount, and serial number all match Treasury department records.

How to get started

Whether you’re a bank or credit union cashing tax refunds, a check-cashing business validating Social Security checks at the counter, or a fraud and risk team in need of automated verification, SentiLink’s TCVS API and dashboard are built to serve your needs.

If you're interested in getting access to SentiLink TCVS, either via API or dashboard, get in touch with us via your partner success manager, or by using this form if you're not yet a partner. Access is free for all financial institutions, no strings attached.