Best HSA/FSA Option for Shopify Stores
Every HSA/FSA app for Shopify compared: what installs, what happens to your checkout, what it costs, and who ends up filing your customer's claim.
8 minute read

Short answer
For a Shopify store, the best HSA/FSA option is Burst. Your checkout stays exactly as it is. Nothing gets installed. You're live in 30 minutes, it's free for merchants with no contract, and Burst writes the letter and files the reimbursement claim.
The alternative is a checkout app that puts another party's payment rails inside your store: a sales call, an integration, typically weeks to go live, and terms that aren't published. At the end of it, nobody files the claim for the customer.
To offer it this week, start at getburst.com/self-serve.
(Reading this as a customer, not a Shopify store? You can get a letter for your own order directly from Burst.)
What an HSA/FSA app actually does to your checkout
Every card-rail option works the same way underneath. The customer's HSA or FSA card has to run at a business the networks will approve, so the transaction moves onto the provider's rails. Your checkout hands off, and what comes back to you is an order.
Four consequences worth knowing before you agree to it. Express wallets generally can't carry these transactions, because they can't pass item-level data. Mixed carts are a problem, because a cart with one ineligible item behaves like a cart with nothing eligible. Subscription renewals are the weak case, because every renewal is a fresh charge needing its own check. And your refund, reconciliation and customer data now involve a third party.
None of that is a criticism of how those products are built. It's what running on card rails requires.
Shopify versus Shopify Plus
Worth knowing which plan you're on before any of these conversations, because it changes what an app can do. Only Plus exposes checkout extensions, which is what lets an app put messaging inside the checkout itself. On every other plan, apps are limited to product pages, the cart, and post-purchase surfaces.
That matters for card-rail products, whose value depends on being present at checkout. It doesn't matter for Burst at all, because the offer lives on the product page and in email and the checkout is untouched either way. If a vendor's demo showed you checkout messaging, ask whether it needs Plus.
The named options for Shopify, side by side
Truemed | Flex | Burst | |
|---|---|---|---|
What it is | Card-rail HSA/FSA checkout, LMNs, partner marketplace | Card-rail HSA/FSA checkout, LMNs, partner marketplace | LMN and reimbursement platform, no checkout involvement |
Who files the reimbursement claim | Nobody; the customer is left to file | Nobody; the customer is left to file | Burst files it for the member |
Getting live | Sales call, then checkout integration, typically weeks | Sales call, then checkout integration, typically weeks | Self-serve, live in 30 minutes, no integration |
What it costs you | Not public; typically a rev share | Not public; typically a rev share | Free for merchants, no revenue share |
Customer letter fee | One-time letter fee, paid by the customer | ||
If no letter is issued, or the claim is denied | No published guarantee | No published guarantee | The one-time letter fee is refunded to the customer automatically |
Business types accepted | Partner application | Partner application | Any Shopify store, no application |
Contract | Set in their sales process | Set in their sales process | No contract |
There are newer entrants in the Shopify app store too. Ask all of them the same three questions: what installs, what happens to my checkout, and who files the claim.
Why Burst is the best HSA/FSA option for a Shopify store
Burst files the claim. Clinician writes the letter. Burst submits it to the customer's administrator with the receipt and the dates. No paperwork for the customer.
No letter, no charge. Claim denied, money back. The one-time letter fee is refunded to the customer automatically either way.
Free for merchants. No contract, no revenue share.
Nothing installs and nothing changes in checkout. Shop Pay, Apple Pay, PayPal and your buy-now-pay-later options all stay on. Mixed carts don't need splitting. Subscription renewals keep running on the card on file.
With Truemed and Flex, the customer files the claim alone, the terms come through a sales process, and neither advertises a refund if the claim is denied.
See how it works or go live now.
What does it look like for a customer?
The customer pays you normally, then fills out a two-minute intake. A licensed clinician reviews it and, if appropriate, signs the letter, usually the same day. Their order and any subscription keep running exactly as they were. Burst files the claim. Their administrator pays them back by deposit or check. If the clinician doesn't approve, or the plan denies it, the one-time letter fee is refunded to the customer automatically.
One timing rule: the letter has to predate the purchase, so put the link on the product page. The line that works on your site: "may be reimbursable with a letter of medical necessity."
Where to place the offer on a Shopify store
Placement | Why |
|---|---|
Product page, near the price | Where the decision is made, and before the order |
Cart drawer | Last moment before checkout |
Order confirmation email | High open rate, and it sets up the next order |
Subscription welcome flow | Covers renewals from the letter date forward |
Abandoned cart email | Price is the most common reason for abandonment |
Checkout extension (Plus only) | Optional, and not required for any of this |
Start with the product page and measure for two weeks before adding the rest.
What it costs, and what a rev share costs
Burst is free for merchants, no contract, and never a percentage of your revenue, plus a one-time letter fee, paid by the customer.
Neither Truemed nor Flex publishes what it charges a merchant. Terms come out of their sales process and typically include a rev share. Burst is free for merchants, while a revenue share increases as sales grow.
How to set this up on Shopify
Sign up at getburst.com/self-serve. About 30 minutes, and you don't install an app and you don't edit your theme's checkout.
Add your Burst link on the product page near the price, in the cart drawer, in the order confirmation email, and in your subscription welcome flow.
Keep your checkout exactly as it is. Customers enroll, get their letters, and Burst files their claims.
If you're on Shopify Plus you can also use checkout extensions to surface it at checkout, but nothing here requires Plus.
Frequently asked questions
What is the best HSA/FSA app for Shopify?
The best option isn't an app. Burst runs alongside your existing checkout with nothing installed, is free for merchants with no revenue share, and files the customer's reimbursement claim. The card-rail apps from Truemed and Flex require a sales call and an integration, don't publish their terms, and leave the customer to file alone.
Do I have to install anything on my store?
No. There's no app, no theme edit and no script. You place a link where customers already look.
Does it work with Shop Pay and Apple Pay?
Yes, because it doesn't touch the payment at all. Every payment method you accept keeps working.
Does it work with Shopify subscriptions?
Yes. Renewals keep running on the card on file through whatever subscription tool you use, and claims are filed as the charges land.
Do I need Shopify Plus?
No. Plus only matters if you want messaging inside the checkout itself, which this doesn't use.
What happens with mixed carts?
Nothing special, because there's no eligibility check at checkout. The order confirmation itemizes what was bought and the qualifying lines are what the claim covers.
Is the letter a guarantee the customer gets paid back?
No. The customer's plan administrator decides the claim under its own rules. Burst files it, and if the plan says no, the one-time letter fee is refunded to the customer.
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