HSA/FSA payments, simplified

Attract new customers, grow your cart size, and increase conversion by accepting HSA/FSA payments

Trusted by

    • Stellar Sleep
    • Crossfit Potrero Hill
    • Crossfit Mission Bay
    • Crossfit Brit
    • PowerPlay
    • Oto

Grow your business with Flex

    • Audience

      60M People

      Nearly 1 in 5 Americans have a HSA or FSA account.

    • Growth


      The number of HSAs is up 400% since 2011 and continues to grow.

    • Market

      $125B+ USD

      Available money in HSA/FSAs to be spent on health related purchases.

Built for developers, by developers

Flex provides a prebuilt, hosted checkout page or UI building blocks to integrate HSA/FSA payments directly into your existing payments flow.

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A seamless checkout experience

    • Best in class UX

      A checkout flow designed to make HSA/FSA payments first class citizens, optimized for conversion.

    • Powerful Analytics

      Understand HSA/FSA payments as a channel for growth with Flex’s unique reporting capabilities.

    • Compliant By Default

      Flex verifies HSA/FSA elegibility and maintains records for IRS compliance.

We're here to help

Connect with Flex to understand your HSA/FSA eligibilty and start accepting payments.

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Frequently asked questions

If you can’t find what you’re looking for, please reach out to

    • What are HSA or FSA accounts?

      HSAs (Health Savings Account) and FSAs (Flexible Savings Accounts) are accounts that allow you to set aside pre-tax money to be spent on health related purchases. On average, consumers save 30% on health related purchases by using HSA/FSA funds.

      • What can HSA or FSA funds be spent on?

        HSA/FSA funds can be spent on products or services related to the diagnosis, cure, mitigation, treatment, or prevention of disease. Today, most people spend their HSA/FSA funds on doctor visit copays and pharmacy items but there are many direct to consumer health and wellness products and services that may also qualify.

        • Why can't I just accept HSA/FSA cards in my existing checkout flow?

          • It depends on your business! If you are a ecommerce store selling HSA/FSA eligible items, you are required by the IRS to use an Inventory Information Approval System (IIAS). This system must auto-substantiate HSA/FSA transactions at the point of sale in order for consumers to use their HSA/FSA cards.
          • If you are a wellness business (fitness, nutrition, sleep etc), your product or service may not be explicitly eligible by the IRS. Consumers must receive a Letter of Medical Necessity from a physician deeming your product medically necessary before you can accept HSA/FSA funds.
          • The good news is that Flex can help in either situation. If you aren't sure about your use case, we're happy to chat and explore your specific needs.