How to get FSA/HSA receipts and documentation
Last updated: February 18, 2026
When you make a purchase using Flex to pay with your HSA/FSA card, you'll automatically receive an itemized receipt via email shortly after checkout is completed. This receipt contains all the necessary information for FSA/HSA reimbursement or record-keeping purposes.
What you'll receive
Depending on your purchase, you may receive:
Itemized receipt - Shows product description, price, shipping, and tax costs (sent to all customers)
Letter of Medical Necessity (LOMN) - Required only for "dual-purpose" products that have both cosmetic and medical uses
If you can't find your receipt
If you didn't receive your receipt or can't locate it:
Check your spam/junk folder for emails from
notifications@withflex.comContact support@withflex.com to request a fresh copy
Important: You must use Flex at checkout
We can only provide FSA/HSA documentation if you selected "Flex | Pay with HSA/FSA" as your payment method during checkout. If you paid with a regular credit card or directly through the merchant, we cannot provide receipts or documentation since we did not process your transaction.
Auto-substantiated vs. dual-purpose products
The IRS recognizes two categories of products:
Auto-substantiated items - Products with only medical use that are automatically eligible. These only require an itemized receipt.
Dual-purpose items - Products with both cosmetic and medical uses. These require a Letter of Medical Necessity to confirm medical use.
For auto-substantiated items, Flex's system is not set up to generate a Letter of Medical Necessity since it's not required by the IRS.
If your FSA requests additional documentation
If your FSA administrator requests more detailed product descriptions or additional information, contact our support team. We can sometimes provide updated receipts with more robust product descriptions to help with your claim.
All documentation adheres to strict IRS standards and cannot be customized beyond what's required for compliance.