Letters of Medical Necessity (LMNs) – What Merchants Need to Know
Many FSA/HSA-eligible products require a Letter of Medical Necessity (LMN). Learn why they matter, how they impact your catalog, and how Burst makes LMNs automatic for Shopify brands.
8 minute read
Letters of Medical Necessity (LMNs): What Merchants Need to Know
Turn LMN-required products from compliance headaches into revenue drivers.
If you're a Shopify merchant selling health and wellness products, there's a good chance that some of your most valuable SKUs require a Letter of Medical Necessity (LMN) for FSA/HSA reimbursement.
Ignore them, and you risk lost revenue and frustrated customers. Handle them correctly, and you unlock an entire category of FSA/HSA spending most brands avoid.
This guide explains what LMNs are, why they matter, and how Burst makes them seamless.
What is a Letter of Medical Necessity (LMN)?
An LMN is a document signed by a licensed healthcare provider stating that a product or service is medically necessary for a specific individual.
It's required for many “gray area” FSA/HSA products — items that support health but aren't automatically considered medical under IRS §213(d).
Examples of LMN-required products:
Nutritional supplements and probiotics
Fitness programs, gyms, and exercise equipment
Sleep aids and stress management tools
Alternative therapies (e.g., acupuncture, massage devices)
Important Clarification:
Products do not need to be FDA approved to qualify as FSA/HSA eligible. Eligibility is based on IRS §213(d), not FDA regulation.
If an LMN is required, the onus falls on the healthcare provider to determine and certify medical necessity. Merchants aren't responsible for making this call — their role is to set clear expectations and enable the process.
Why LMNs Matter for Merchants
High-margin SKUs: Many LMN-required products drive higher AOV and LTV.
Large portion of catalog: For many brands, LMN products represent 30–50% of eligible inventory.
Compliance risk: Marketing products as “FSA/HSA eligible” without noting LMN requirements risks TPA audit issues.
Customer frustration: Shoppers abandon carts if they discover post-purchase they can't get reimbursed.
Handled correctly, LMNs become a growth lever instead of a blocker.
The Merchant Challenge: LMNs Without Burst
Traditionally, LMNs create friction:
Customers must book a doctor's appointment for a signed form.
Processing delays stretch into days or weeks.
Many shoppers give up before completing reimbursement.
Result: Merchants avoid LMN SKUs altogether, leaving money on the table.
How Burst Makes LMNs Seamless
Burst automates LMNs so merchants can safely promote LMN-required products without friction.
Automatic LMN generation: Shoppers complete a quick telehealth intake post-purchase.
<24 hour turnaround: LMNs are delivered back almost instantly.
One LMN = recurring coverage: For subscriptions, Burst generates one LMN and applies it across all renewals.
Audit-ready compliance: All LMNs align with IRS §213(d) and TPA standards.
High approval rates: Burst collaborates directly with healthcare providers and TPAs to understand the conditions that make products medically necessary — resulting in fewer denials.
LMNs Without Burst vs With Burst
Factor | Without Burst | With Burst |
|---|---|---|
Process | Customer books doctor's visit, waits for signed form | Quick online intake, LMN generated in <24 hrs |
Customer effort | High — paperwork, scheduling, follow-ups | Low — handled automatically post-purchase |
Subscription coverage | New LMN needed each renewal | ✅ One LMN applies across all renewals |
FDA approval requirement | Often assumed necessary | ✅ Not required — eligibility comes from IRS §213(d) + provider certification |
Onus | Falls awkwardly on shopper to secure | Properly falls on healthcare provider, with Burst managing intake |
Approval rates | Low — generic doctor notes often denied | ✅ High — Burst works with providers + TPAs for alignment |
Merchant compliance risk | High if misrepresented | ✅ Audit-ready, IRS/TPA aligned |
Takeaway: LMNs without Burst = friction + lost sales. With Burst = compliance, conversion, and retention.
How to Build Awareness Around LMN Products
Transparency makes LMNs a selling point, not a blocker.
Best Practices:
Badge PDPs: 📄 “FSA/HSA Eligible with LMN (auto-generated by Burst).”
Add PDP copy: “This product requires a doctor's note (LMN) for reimbursement. We'll handle it automatically.”
Cart nudges: “Don't worry — Burst will generate your LMN post-purchase.”
Order confirmation emails: Reinforce: “Burst is generating your LMN — no action required.”
LMNs as a Competitive Advantage
Most merchants avoid LMN products because they seem complicated. That's why leaning into them is a chance to stand out.
Differentiate your store: Few brands confidently market LMN eligibility.
Increase retention: Shoppers trust merchants who make benefits easy.
Expand catalog: More SKUs can be safely marketed as FSA/HSA eligible.
LMNs aren't a blocker — they're an unlock.
How Burst Powers LMN Compliance + Growth
With Burst:
LMNs are auto-generated in <24 hours
Coverage applies across recurring subscriptions
Merchants stay audit-ready
Customers avoid paperwork while providers issue LMNs responsibly
Approval rates stay high because Burst works hand-in-hand with healthcare providers and TPAs
👉 Want to expand your catalog without compliance risk? See how Burst works for brands.
Merchant FAQ: LMNs Made Simple
Do LMNs expire?
Yes, most LMNs are tied to a specific condition and period of treatment. Some TPAs require renewal annually, while others accept multi-year LMNs. With Burst, shoppers are automatically prompted if their LMN needs refreshing — no guesswork for you or your customers.
Can one LMN cover multiple products?
Sometimes. If the healthcare provider certifies that multiple products are part of treating the same condition (e.g., probiotics + supplements for digestive health), one LMN may cover them all. Burst works with providers and TPAs to maximize coverage.
What if a shopper subscribes to a product that requires an LMN?
With Burst, the LMN is generated once and then applied to all future subscription renewals. Shoppers don't need to re-submit paperwork every month.
What if a shopper's claim gets denied?
Denials usually happen because the LMN wasn't specific enough. Burst minimizes this risk by collaborating directly with healthcare providers and TPAs to ensure LMNs use language and conditions that meet approval standards.
Does the product need FDA approval to qualify?
No. Eligibility is based on IRS §213(d), not FDA regulation. As long as a licensed healthcare provider determines the product is medically necessary and issues an LMN, it can qualify for reimbursement.
Who is responsible for the LMN?
The responsibility lies with the healthcare provider who signs the LMN. Merchants are not responsible for determining medical necessity. Burst handles the intake and provider workflow so this process stays compliant and effortless.
Do LMNs create liability for my brand?
No. Because the onus is on the provider, not the merchant, you aren't liable for medical determinations. Your responsibility is only to clearly communicate when a product requires an LMN, which Burst makes simple with automated badging.
What types of products usually require LMNs?
Nutritional supplements
Fitness programs, gyms, exercise equipment
Sleep and stress aids
Alternative therapies and devices
These are some of the most valuable SKUs for merchants — and Burst unlocks them.
Next Steps
Audit your catalog: identify LMN-required SKUs.
Badge PDPs and cart with clear LMN messaging.
Use Burst to automate LMN generation and ensure audit compliance.
Confidently market LMN products as part of your FSA/HSA collection.
The Bottom Line: LMNs don't need to be a barrier. With Burst, they become a competitive advantage — unlock more revenue, avoid compliance headaches, and grow your catalog without worry.
