Announcements
Flex + Silver: Making Letters of Medical Necessity Simple for TPAs and Consumers
Flex is transforming how people use their HSA and FSA funds by making payments simple, seamless, and accessible. Partnering with Silver, the AI platform for claims automation, we’re helping TPAs cut delays and giving consumers a smoother experience on purchases that require a Letter of Medical Necessity.
September 10, 2025
Sam O'Keefe
Co-founder & CEO of Flex
Overview
Overview
Overview
At Flex, our mission is to improve health by making consumer-directed spending simple, seamless, and ubiquitous, working directly with retailers to add Health Savings Account (HSA) and Flexible Spending Account (FSA) payments as an option at checkout. That’s why we’ve partnered with Silver, the AI platform automating benefit claim processing for TPAs, to fix one of the most frustrating pain points: purchases requiring a Letter of Medical Necessity (LMN).
The problem with dual-use purchases
When consumers purchase products that can serve both medical and non-medical purposes, such as fitness equipment and programs, supplements, home devices, or red light therapy, the substantiation process quickly becomes complex. According to IRS rules, TPAs must collect not only an itemized receipt but also a clinician’s letter verifying the medical necessity.
This additional requirement often leads to delays, repeated documentation requests, and participant frustration. In some cases, an FSA card may even be suspended if the claim is not substantiated in a timely manner.
How Flex and Silver work together
Here’s what the new experience looks like:
A plan participant makes a purchase with Flex at a retailer.
With the participant’s permission, Flex guides them through a quick, compliant workflow to verify eligibility and collect a LMN.
Silver flags that transaction inside the TPA’s claims system.
Silver securely retrieves the receipt and the LMN from Flex.
The TPA’s claims team can review the documentation right away without asking the participant for more paperwork.
The result? Fewer back-and-forth emails, faster decisions, and claims that close in hours instead of weeks.
Why this matters
Less manual work: Administrators don’t have to chase down receipts or LOMNs.
Fewer delays: Consumers get to move on with their day instead of resubmitting documents.
Better compliance: TPAs get complete, standardized documentation that aligns with IRS guidance.
Built on proven automation
Silver’s customers already cut claim processing times in half by using AI to read receipts, match eligible expenses, and auto-approve straightforward claims. Now, those time savings extend to LMN scenarios.
“LMNs are a classic source of churn: multiple emails, vague receipts, and disappointed consumers. By detecting LMN-required transactions up front and pairing that with Flex’s streamlined flow, we’re removing friction for consumers, TPAs, and retailers,” said Oded Shekel, Co-founder and CEO of Silver.
What’s next
The Silver and Flex LOMN workflow is already in pilot with select TPAs, with broader availability and integration resources coming soon.
“Our mission is to make HSA and FSA spending simple and compliant. Working with Silver lets us meet consumers where they are and gives TPAs complete, audit-ready documentation without scavenger hunts,” said Sam O’Keefe, Co-founder and CEO of Flex.
TPAs interested in participating can schedule a demo with Silver. Retailers or brands interested in offering HSA/FSA as a payment method can contact Flex.
At Flex, our mission is to improve health by making consumer-directed spending simple, seamless, and ubiquitous, working directly with retailers to add Health Savings Account (HSA) and Flexible Spending Account (FSA) payments as an option at checkout. That’s why we’ve partnered with Silver, the AI platform automating benefit claim processing for TPAs, to fix one of the most frustrating pain points: purchases requiring a Letter of Medical Necessity (LMN).
The problem with dual-use purchases
When consumers purchase products that can serve both medical and non-medical purposes, such as fitness equipment and programs, supplements, home devices, or red light therapy, the substantiation process quickly becomes complex. According to IRS rules, TPAs must collect not only an itemized receipt but also a clinician’s letter verifying the medical necessity.
This additional requirement often leads to delays, repeated documentation requests, and participant frustration. In some cases, an FSA card may even be suspended if the claim is not substantiated in a timely manner.
How Flex and Silver work together
Here’s what the new experience looks like:
A plan participant makes a purchase with Flex at a retailer.
With the participant’s permission, Flex guides them through a quick, compliant workflow to verify eligibility and collect a LMN.
Silver flags that transaction inside the TPA’s claims system.
Silver securely retrieves the receipt and the LMN from Flex.
The TPA’s claims team can review the documentation right away without asking the participant for more paperwork.
The result? Fewer back-and-forth emails, faster decisions, and claims that close in hours instead of weeks.
Why this matters
Less manual work: Administrators don’t have to chase down receipts or LOMNs.
Fewer delays: Consumers get to move on with their day instead of resubmitting documents.
Better compliance: TPAs get complete, standardized documentation that aligns with IRS guidance.
Built on proven automation
Silver’s customers already cut claim processing times in half by using AI to read receipts, match eligible expenses, and auto-approve straightforward claims. Now, those time savings extend to LMN scenarios.
“LMNs are a classic source of churn: multiple emails, vague receipts, and disappointed consumers. By detecting LMN-required transactions up front and pairing that with Flex’s streamlined flow, we’re removing friction for consumers, TPAs, and retailers,” said Oded Shekel, Co-founder and CEO of Silver.
What’s next
The Silver and Flex LOMN workflow is already in pilot with select TPAs, with broader availability and integration resources coming soon.
“Our mission is to make HSA and FSA spending simple and compliant. Working with Silver lets us meet consumers where they are and gives TPAs complete, audit-ready documentation without scavenger hunts,” said Sam O’Keefe, Co-founder and CEO of Flex.
TPAs interested in participating can schedule a demo with Silver. Retailers or brands interested in offering HSA/FSA as a payment method can contact Flex.
Flex is the easiest way for direct to consumer brands and retailers to accept HSA/FSA for their products. From fitness and nutrition, to sleep and mental health, Flex takes a holistic view of healthcare and enables consumers to use their pre-tax money to do the same.