Flex
Stripe for HSA/FSA payments
Founded 2023 · $18.0M raised
- Employees
- 1–10
- Founded
- 2023
- Website
- withflex.com
- Total Funding
- $18.0M
- Last Round
- $15.0M Series ASep 2025
- Rounds
- 2
About
Flex is a payment platform for businesses to accept HSA/FSA, unlocking the $150B per year sitting in HSA/FSA accounts.
Summary
Flex is a Fintech company, founded in 2023. It has raised $18.0M in total across 2 rounds, most recently a $15.0M Series A round in Sep 2025. Investors include Y Combinator Continuity Fund and First Round Capital.
Tech & App Stack
26 technologies & apps tracked
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Funding History
Sep 2025
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Full funding history, per-round amounts, and investor participation.
Investors
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