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Letter of Medical Necessity Template

Fill in the form and get a complete letter of medical necessity to copy or print. Free, no signup. The letter is built in your browser: PatientNotes never receives or stores what you type.

Insurance

Patient

Request and Diagnosis

Clinical Justification

Prescriber

Your Letter of Medical Necessity

Updates as you type. Blanks in [brackets] stay until you fill them in. Built in your browser; PatientNotes never receives or stores what you type.

[Date]

[Insurance company or plan name]
Attn: [Utilization review / medical review department]
[Address or fax number]

RE: Letter of Medical Necessity
Patient: [Patient name]
Date of birth: [MM/DD/YYYY]
Member ID: [Member ID]
Requested: [item, medication or service]
CPT/HCPCS code(s): [Code(s)]
Diagnosis: [diagnosis] (ICD-10: [Code(s)])

Dear Medical Reviewer,

I am writing on behalf of my patient, [Patient name], to request coverage of [item, medication or service] for the treatment of [diagnosis].

Clinical history
[Relevant history, symptoms, exam and test results, and functional limitations]

Why this is medically necessary
[How the requested item or service treats the condition and why this one is needed]

Alternatives tried
[Each treatment tried, with dates or duration, and why it failed, was not tolerated or is contraindicated]

Expected outcome
[Treatment goal and how progress will be measured]

In my clinical judgment, [item, medication or service] is medically necessary for [Patient name].

Please contact my office at [phone] if you need any further information.

Sincerely,


[Prescriber name, credentials]
NPI: [NPI number]

Free letter of medical necessity template

Prefer your own letterhead? Copy this template and replace each item in [brackets].

[Date]

[Insurance company or plan name]
Attn: [Utilization review / medical review department]
[Address or fax number]

RE: Letter of Medical Necessity
Patient: [Patient full name]
Date of birth: [MM/DD/YYYY]
Member ID: [Member ID]   Group number: [Group number]
Requested item or service: [Item, medication or service]
CPT/HCPCS code(s): [Code(s)]
Diagnosis: [Diagnosis] (ICD-10: [Code(s)])

Dear Medical Reviewer,

I am writing on behalf of my patient, [Patient name], to request coverage of [item, medication or service] for the treatment of [diagnosis]. I have treated [Patient name] since [date].

Clinical history
[Relevant history, onset, severity, current symptoms, examination and test results, and how the condition limits daily function.]

Why this is medically necessary
[How the requested item or service treats the condition and why this specific item, dose, frequency or duration is needed for this patient.]

Alternatives tried
[Each treatment tried, with dates or duration, and why it failed, was not tolerated or is contraindicated.]

Expected outcome
[The goal of treatment and how progress will be measured.]

In my clinical judgment, [item, medication or service] is medically necessary for [Patient name]. Supporting records are enclosed: [office notes, test results, imaging reports, therapy notes].

Please contact my office at [phone] or [fax] if you need any further information.

Sincerely,

[Prescriber name, credentials]
NPI: [NPI number]
[Practice name]
[Practice address, phone, fax]

What a letter of medical necessity should include

Payers set their own requirements, so check the payer's policy for the item or service. Most letters cover the same ground:

  1. 1. Patient and insurance details

    Full name, date of birth, member ID and group number exactly as they appear on the insurance card, so the letter can be matched to the right claim or request.

  2. 2. Diagnosis with ICD-10 codes

    The condition being treated, in words and as ICD-10-CM codes. Use the most specific code the record supports; a vague code makes the request harder to match to coverage criteria.

  3. 3. The requested item or service, with codes

    Name the exact item, medication or service, with the CPT or HCPCS code where one applies, plus the quantity, dose, frequency or duration you are requesting.

  4. 4. Clinical history

    Onset, severity and course of the condition, relevant exam and test findings, and how it affects daily function. Reviewers look for the facts that match their coverage criteria.

  5. 5. Why it is necessary

    Explain how the requested item or service treats the condition, and why this particular one (rather than a cheaper or simpler option) is right for this patient.

  6. 6. Alternatives tried and why they failed

    List each prior treatment with dates or duration and the result: ineffective, not tolerated, or contraindicated. Without it, a reviewer cannot tell why a simpler option will not do.

  7. 7. Expected outcome

    The treatment goal and how you will measure it. Where it helps, say what is likely to happen without the requested treatment.

  8. 8. Prescriber signature and NPI

    Signed by the treating clinician, with credentials, NPI, practice name and contact details, and a list of enclosed supporting records.

Look up codes with the ICD-10 code lookup and the CPT and HCPCS lookup.

Letter of medical necessity examples

Fill-in-the-blank examples for common requests. They show what each section should say; every patient detail is a blank for you to complete from the chart. Use them with the template above.

Durable medical equipment: CPAP

For a patient with obstructive sleep apnea who needs a CPAP device and supplies.

Requested item: CPAP device and supplies (HCPCS: [device and supply codes])
Diagnosis: Obstructive sleep apnea (ICD-10: [code, e.g. G47.33])

Clinical history
[Patient name] reports [symptoms, e.g. loud snoring, witnessed apneas, daytime sleepiness]. A [type of sleep study] on [date] showed [AHI or RDI result and oxygen saturation findings].

Why this is medically necessary
CPAP is the treatment I am prescribing for [Patient name]'s obstructive sleep apnea at [pressure setting or auto range]. Untreated, [describe the risks relevant to this patient, e.g. daytime sleepiness affecting work or driving, cardiovascular comorbidities].

Alternatives tried
[e.g. positional therapy, weight-loss counselling, oral appliance: what was tried, for how long, and the result.]

Expected outcome
[e.g. reduced daytime sleepiness and improved sleep quality, reviewed at follow-up with device usage data.]

Check the payer's policy for what it requires with a CPAP request, such as the sleep study report and, for continued coverage, usage data.

Durable medical equipment: power wheelchair

For a patient who cannot safely use a cane, walker or manual wheelchair at home.

Requested item: Power wheelchair, [base type and options] (HCPCS: [codes])
Diagnosis: [Diagnosis] (ICD-10: [code(s)])

Clinical history
[Patient name] has [diagnosis] with [describe strength, range of motion, endurance, balance, pain and falls]. At the examination on [date], [describe the mobility findings].

Why this is medically necessary
[Patient name] cannot complete [mobility-related daily activities, e.g. toileting, meals, dressing] in the home without a power wheelchair. [Patient name] is able to operate a power wheelchair safely and the home allows its use: [describe].

Alternatives tried
Cane or walker: [why it is insufficient or unsafe]. Manual wheelchair: [why the patient cannot self-propel, e.g. upper-body strength or endurance]. Scooter: [why it is not suitable, e.g. trunk stability or home layout].

Expected outcome
[e.g. independent completion of mobility-related daily activities in the home and reduced fall risk.]

Check the payer's policy, which may require a specific face-to-face examination and a written order before the letter is considered.

Specialty medication

For a medication that needs prior authorization or step-therapy exception.

Requested medication: [Drug name, strength, dose, route, frequency] (HCPCS: [J-code, if billed as a medical benefit])
Diagnosis: [Diagnosis] (ICD-10: [code(s)])

Clinical history
[Patient name] was diagnosed with [diagnosis] on [date]. Current disease activity: [objective measures, e.g. scores, labs, imaging, frequency of flares or hospital visits].

Why this is medically necessary
[Drug name] is indicated for [diagnosis] and is appropriate for [Patient name] because [reason, e.g. disease severity, comorbidities, contraindications to other options]. [Cite the guideline or evidence you are relying on.]

Alternatives tried
1. [Drug], [dose], from [date] to [date]: [inadequate response / adverse effect / contraindication].
2. [Drug], [dose], from [date] to [date]: [result].

Expected outcome
[Treatment goal, e.g. reduced disease activity measured by [measure] at [interval].]

If the plan has a formulary exception or step-therapy exception process, check the payer's policy for the form it wants alongside the letter.

Physical therapy extension

For more visits after the initial authorized course of therapy.

Requested service: Physical therapy, [number] additional visits over [weeks] (CPT: [codes, e.g. 97110, 97140])
Diagnosis: [Diagnosis] (ICD-10: [code(s)])

Clinical history
[Patient name] began physical therapy on [date] for [diagnosis] after [injury or surgery, if any]. Baseline: [measures, e.g. range of motion, strength, a validated functional score]. Current: [the same measures today].

Why this is medically necessary
[Patient name] has made measurable progress but has not reached the goals set at evaluation: [goals not yet met]. Continued skilled therapy is needed for [specific skilled interventions], which cannot yet be done safely as a home program because [reason].

Alternatives tried
[e.g. home exercise program alone, medication, injection: what was tried and the result.]

Expected outcome
[Specific, measurable goals for the extension, e.g. target range of motion or functional score, and a discharge plan to a home program.]

Showing the same measures at baseline and now makes progress, and the need for more visits, easy for a reviewer to see.

Frequently asked questions

What is a letter of medical necessity?

A letter of medical necessity (LMN) is a letter from the treating clinician explaining why a patient needs a specific item, medication or service. It is used to support prior authorization requests, appeals of denied claims, equipment orders and similar requests to an insurer or plan.

Who writes and signs a letter of medical necessity?

The treating clinician who orders the item or service signs it, usually a physician, nurse practitioner or physician assistant, or another licensed clinician where the payer accepts one. Office staff often draft the letter from the chart, and the clinician reviews, edits and signs it.

How is it different from a prior authorization request?

Prior authorization is the payer's approval process, and many payers have their own request form. A letter of medical necessity is the clinician's narrative that supports that request, or an appeal after a denial. Use our prior authorization letter generator for the request itself, and this template when the payer or supplier asks for a letter of medical necessity.

Can I use this template to appeal a denial?

Yes. Add the claim or reference number and the date of the denial, quote the reason given in the denial letter, and answer that reason directly in the clinical sections. Check the payer's policy for its appeal deadline and where to send the appeal.

How long should a letter of medical necessity be?

As long as the case needs and no longer. One to two pages is typical. Put the facts a reviewer needs (codes, history, alternatives tried) where they are easy to find, and enclose the supporting records rather than copying them into the letter.

Does a letter of medical necessity guarantee coverage?

No. Coverage depends on the plan and its medical policy for the item or service. Check the payer's policy for its coverage criteria and required documents, and make sure the letter addresses each criterion.

Is a letter of medical necessity the same as a certificate of medical necessity?

Not always. Some payers and equipment suppliers use their own standard forms for certain items. Check the payer's policy, or ask the supplier, whether they need a specific form in addition to or instead of a letter.

Does PatientNotes see what I type on this page?

No. The letter is built in your browser as you type. PatientNotes never receives or stores what you enter; refreshing or closing the page clears the form. Even so, use blanks or initials rather than full patient identifiers until you paste the letter into your own records.

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