Pet insurance claim denied for a pre-existing condition? How to appeal it

What the insurer is actually saying

A pre-existing condition denial means the insurer believes your pet had the problem, or showed signs of it, before your cover started or during the waiting period. Nearly every accident-and-illness policy excludes pre-existing conditions, so the question is rarely whether the exclusion exists. The question is whether it applies to this claim.

That judgment is usually made by a claims reviewer reading your vet notes. Notes are written quickly, in shorthand, for the vet's own use. A single entry like “intermittent vomiting” or “mild lameness, monitor” can be read as the start of an illness diagnosed months later, even when the two have nothing to do with each other.

Find the exact visit they are relying on

Read the denial letter line by line. A well-written letter names the date of the earlier visit, the symptom it relies on, and the policy section that defines a pre-existing condition. Write all three down. If the letter does not name a visit or a clause, ask for both in writing before you do anything else; you cannot answer a reason you have not been given.

Then request your pet's complete medical record from every clinic it has visited, including emergency hospitals and the shelter or breeder if records came with your pet. Ask for the clinical notes, not just invoices. Read the visit the insurer cites with the denial letter beside you.

Test the insurer's reasoning against the records

You have a strong appeal when one or more of these is true:

• The earlier visit concerned a different part of the body or a different system — an ear infection versus a later stomach problem, a skin rash versus a later knee injury.
• The earlier problem resolved, and the notes say so: “resolved,” “normal on recheck,” “no abnormalities.”
• The cited symptom is common and vague, appeared once, and your vet does not connect it to the diagnosis.
• The new condition has an obvious new cause, such as an accident, a swallowed object or a specific injury.
• Your policy paid for this same condition in an earlier policy year.
• Your policy treats some conditions as “curable” and covers them again after a symptom-free period, and that period has passed.

When the denial is probably right

Be honest with yourself here. If the notes record the same condition, in the same part of the body, before your cover began, and your vet agrees it is the same problem, an appeal is unlikely to succeed. That is useful to know too: it tells you exactly what your policy will and will not cover before your next renewal.

Get your vet to answer the medical question

Most pre-existing disputes are medical, not legal: was the March symptom connected to the July illness? Your vet examined your pet; the insurer's reviewer did not. A short signed statement from your vet is often the single strongest piece of evidence you can send.

Make it easy for a busy clinic. Draft a one-page statement yourself with three numbered points: what the earlier visit was for and how it ended, when the claimed condition was first diagnosed, and whether, in the vet's opinion, the two are related and why. Ask your vet to correct anything that is not accurate and sign it. Never ask a vet to sign something they do not believe; if they think the conditions are related, accept that answer.

Write the appeal in one page

A strong appeal is short, calm and specific. Quote the insurer's reason in its own words. Then answer it in two or three numbered points, each tied to an enclosed document: the policy start date, what the earlier visit actually showed, and your vet's confirmation that the two conditions are unrelated. Quote the policy's own definition of a pre-existing condition and explain why the facts do not meet it.

Close with a clear request: reverse the denial and pay the claim, or, if they uphold it, send you the specific records and policy wording relied on. That second request matters, because it forces a reasoned answer you can take further. Our step-by-step appeal guide covers how to send it and follow up.

Check whether your state's law helps

A growing number of states have pet insurance laws based on a model act adopted by the National Association of Insurance Commissioners. Where they apply, the insurer generally carries the burden of proving a pre-existing condition exclusion applies, and a condition the policy already covered cannot be excluded at renewal. If you live in one of those states, say so in one sentence in your appeal. Our state-by-state overview lists them.

What to do this week

Today: find your appeal deadline in the denial letter or your policy, and write down the visit and the clause the insurer relies on. Tomorrow: request your pet's full records and the insurer's claim file. Once they arrive, read the cited visit yourself, ask your vet for a short statement, and send a one-page appeal with the evidence attached.

If you would rather not start from a blank page, Denied? The Pet Insurance Appeal Kit includes a ready-to-fill pre-existing condition appeal, the vet statement template, and the claim file request, alongside a worked example of a pre-existing denial from start to finish.