Flex

What Flex is

Flex builds the payment plumbing for tax-advantaged health spending: merchants accept HSA and FSA cards, eligibility gets verified, and compliance documentation is handled in the flow.

What you can do with it

• Accept HSA/FSA payments at checkout
• Verify product eligibility automatically
• Support subscriptions from benefit accounts
• Integrate with Shopify and apps
• Reduce payment declines for health purchases

Who it is for

• Health and wellness e-commerce
• Subscription health services
• Brands serving US benefit account holders

What to watch out for

• Category misplacement: payment infrastructure, not content moderation
• HSA/FSA eligibility rules are US tax law; misclassified purchases create liability for merchants and customers
• Verify the compliance documentation trail survives audits; ask how eligibility letters are stored
• US-only scope by definition; international merchants need not apply