How to write a medical claim appeal letter (template)

Most appeal letter templates online are built around prose: a paragraph of polite disagreement, a request for reconsideration, a hope that someone reads it carefully. Reviewers working a stack of appeals do not read that way. They scan for six specific facts, in a specific order, and a letter organised around those facts gets processed faster than one organised around persuasion.

The six sections, and why each one exists

1. Claim identification. Claim number, date of service, procedure codes and provider name, in the first few lines. A reviewer working hundreds of files needs to locate yours before they can do anything else.
2. The exact denial being disputed. The CARC with its group code, and any paired RARC, written exactly as it appears on the remittance, CO-45 rather than just 45, since that is the string the reviewer's own system is indexed on.
3. A specific, citable ground. The corrective action for that CARC, and why the claim already satisfies it or why the payer's application was wrong. This is the section that actually wins or loses the appeal.
4. Documentation, named rather than attached. Point to the specific record, operative note, or authorisation the reviewer should pull, rather than leaving them to find it inside a stack of attachments.
5. The deadline you are filing inside, stated explicitly. Confirming you are within the window removes the easiest procedural reason to bounce the letter unread.
6. A named, specific request for action. Ask for the claim to be reprocessed, at a stated amount if relevant, not for vague reconsideration.

The template

Copy the structure below and fill in the bracketed fields from your own denial. The [TO BE COMPLETED] placeholders are deliberate: a template that invents plausible-sounding details is worse than one that makes the missing facts obvious, since a reviewer checking a fabricated citation against the actual file is the fastest way to lose credibility on every future letter this practice sends.

Re: Reconsideration request, Claim #[TO BE COMPLETED], Date of Service [TO BE COMPLETED], Patient [TO BE COMPLETED] We are requesting reconsideration of the adjustment reported on the remittance dated [TO BE COMPLETED] under [CARC, e.g. CO-45] for CPT [TO BE COMPLETED]. [State the specific, citable ground here, for example: our current participation agreement, effective (date), sets a different contracted rate for this code than the amount applied, and the relevant fee schedule page is enclosed.] Supporting documentation: [name the specific document, e.g. operative note dated (date), page (X)], enclosed. This request is filed within the (X)-day reconsideration window from the remittance date of [TO BE COMPLETED]. We request the claim be reprocessed at the correct rate/allowed, and payment issued accordingly.

Filling in the ground: three real examples

Before you send it

• Confirm the deadline against the actual payer, not a remembered figure; timely filing and reconsideration windows vary significantly by payer and are separate clocks from each other.
• Read the denial's CARC and RARC pair one more time, since a misread group code or an unrelated RARC can quietly undermine an otherwise solid letter.
• Route the letter to the correct department or fax line. A reconsideration sent to a general claims inbox instead of the payer's specific appeals unit is a common, entirely avoidable delay.

Why a template is not a substitute for judgment

A template gets the structure right every time, but it cannot decide whether a denial is actually worth appealing. That judgment call, whether a CO-45 is a routine write-off or a genuine contract-year error, whether a CO-97 has real documentation behind it, comes first, and our full guide to writing a reconsideration a payer has to answer covers that decision in depth, including current filing deadlines by payer and the industry data on how often a well-argued reconsideration actually succeeds.

Frequently asked questions

Should I use this same template for a second-level appeal?

The same six-section structure still applies, but a second-level appeal, filed after a first reconsideration was already denied, usually carries a higher documentation bar and is reviewed by an independent or specialist reviewer rather than the original claims department. Expect to add more specific supporting evidence than a first-level letter typically needs.

Is it acceptable to send this appeal letter by email instead of fax or mail?

It depends entirely on the specific payer's published appeals process; some accept a secure provider portal submission or email, others still require fax or physical mail to a specific appeals address. Sending a well-written letter to the wrong channel produces the same result as not sending it at all.

Do I need to attach the actual medical record, or is referencing it enough?

Reference it specifically by document name and date, and attach it. Naming the record without including it forces the reviewer to request it separately, adding a round trip; attaching it without naming what it shows forces the reviewer to read the whole record to find the relevant part. Do both.

What if I do not have a specific citable ground yet?

Do not send the letter yet. A reconsideration filed without a specific ground reads as a complaint, not an argument, and can make the practice's future appeals look less credible. Confirm the CARC's actual corrective action and gather the specific document that supports your position first.