How It Works

How a Letter of Medical Necessity Works

A simple walkthrough of how an independent clinician reviews your information, and what to expect at each step.

How Review Works

From health information you share to a decision

Every step is handled by a licensed clinician using their own judgment. It is a genuine clinical assessment, not a formality, and a Letter of Medical Necessity is never guaranteed.

1

Complete the clinical intake

You share relevant health information, including the conditions you've been diagnosed with and the support you're seeking.

Seamless · online
2

A licensed clinician reviews it

An independent clinician, licensed in your state, reviews what you submitted using their own clinical judgment. Our clinicians don't use pre-set rules or make automated approvals. They may follow up by message if they need more information.

Independent · state-licensed
3

A decision is made

If a Letter of Medical Necessity is appropriate for your diagnosed condition and the support you are seeking, the clinician may issue one.

Issued only when appropriate
4

Your LMN is documented

When your clinician issues an LMN, it captures the reasoning behind their recommendation. That documentation supports your HSA/FSA records for any products or services they've determined are right for your condition.

Supports HSA/FSA documentation

What This Is and Isn’t

A focused review, clearly bounded

What a review is

  • A genuine medical assessment by a licensed clinician
  • A provider-patient relationship, focused on your diagnosed condition(s)
  • Based on the information and conditions you share

What it isn’t

  • Not a review of your full medical history
  • Not automated, and never a guaranteed "yes"
  • Not general wellness advice

FAQ

Common questions

An LMN is a licensed clinician's written documentation that a product or service is medically recommended to cure, treat, mitigate, or prevent a specific, diagnosed condition. That documentation can make it eligible for HSA/FSA use.

Truemed is a healthcare-technology company that provides the platform, administrative, and operational support behind Root Cause's review process. Root Cause is an independent clinical practice, and all decisions are made by licensed clinicians, not by Truemed.

An independent clinician, licensed in your state, reviews the information you submit and decides whether an LMN is appropriate.

No. Each decision is made by a licensed clinician using clinical judgment, not an algorithm or an instant rule.

No. An LMN is issued only when it's clinically appropriate for a diagnosed condition. If it isn't the right fit, one isn't issued.

Root Cause's documentation is built to support HSA/FSA substantiation, but acceptance is always the plan administrator's decision.

An LMN is generally valid for 12 months from the date it is issued. After that, a new review may be needed for continued HSA or FSA use.

Truemed's eligibility framework has been independently validated by the Validation Institute. See the For Benefits Administrators page for detail.

View the Validation Institute report →

Root Cause's managed services organization, Truemed, is SOC 2 compliant.

No. Root Cause provides focused review for documentation purposes and is not a substitute for your primary care provider or emergency care.

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FROM OUR RESOURCES

How to get a letter of medical necessity →Who can write a letter of medical necessity →

Validated & Secured

Independently validated, securely run

Independently validated

Truemed’s eligibility framework has been independently validated by the Validation Institute.

Privacy & security

Root Cause’s managed services organization, Truemed, is SOC 2 compliant.