Last updated: August 2026 · Reviewed by Miguel Cibeira
This article is for informational and educational purposes only and is not insurance or veterinary advice. How pre-existing conditions are defined and handled varies by provider and policy — always confirm current terms directly with the insurer.
Nearly every article on this site references pre-existing conditions in passing. This one covers the concept in full — the surprisingly broad definition insurers actually use, the curable-versus-incurable distinction that can determine whether a condition is ever covered again, and the specific rules around bilateral conditions that catch a lot of pet owners off guard.
The Basic Definition
A pre-existing condition is any illness, injury, or symptom your pet showed — whether formally diagnosed or not — before your policy’s start date, or during the waiting period covered in our companion guide on what waiting periods are. This definition is broader than many pet owners initially assume: it’s not limited to conditions your vet formally diagnosed. If you personally noticed a symptom (excessive limping, for example) before enrolling, even without a vet visit at the time, that symptom can still be treated as evidence of a pre-existing condition once an insurer reviews your pet’s medical history later.
The Distinction That Matters Most: Curable vs. Incurable
This is the single most important nuance in how pre-existing conditions actually work, and it’s worth understanding in detail, since it determines whether an excluded condition might ever become coverable again.
Curable conditions are those that fully resolve, with no recurring symptoms or ongoing treatment, for a defined symptom-free period — commonly 180 days, though some insurers require a full year (365 days). Common examples include ear infections, urinary tract infections, upper respiratory infections, and non-chronic vomiting or diarrhea. If a curable condition meets an insurer’s symptom-free threshold, many providers will reconsider that condition eligible for coverage going forward — meaning a pre-existing exclusion for a curable condition isn’t necessarily permanent.
Incurable (or chronic) conditions are those expected to require ongoing management or that carry a meaningful risk of recurrence. Commonly cited examples include arthritis, diabetes, hip dysplasia, most cancers, allergies, many forms of heart disease, torn cruciate ligaments, epilepsy, disc disease, and urinary blockages or cystitis. These generally remain excluded permanently, even if well-managed and symptom-free for an extended period — the “curable” reconsideration process typically doesn’t apply to this category at all.
Why this distinction matters practically: two pets can each have a single pre-existing condition on record, but if one is classified as curable and the other as incurable, their future coverage can look very different. A dog with a resolved ear infection, well past the symptom-free threshold, may see that specific condition become coverable again if it recurs. A dog with diagnosed hip dysplasia will generally see that condition excluded for the life of the policy, regardless of how much time passes.
Bilateral Conditions: The Detail That Surprises Most Pet Owners
This is worth its own dedicated explanation, since it’s one of the most commonly misunderstood aspects of pet insurance. A bilateral condition is one that can affect either side of a paired body part — common examples include hip or elbow dysplasia, cruciate ligament injuries, cataracts, glaucoma, and patellar luxation.
Here’s the part that catches people off guard: if your pet showed symptoms of a bilateral condition on one side of the body before your policy started, many insurers will exclude that same type of condition on the other side as well — even if the other side has never shown any symptoms at all. For example, if your dog was diagnosed with a torn cruciate ligament in the right knee before enrollment, a future torn ligament in the left knee may still be excluded as related to a pre-existing bilateral condition, purely because the condition type is the same, even though the specific leg is different.
This rule generally applies most strictly to incurable bilateral conditions. Some insurers apply more flexibility to curable bilateral conditions — for example, an ear infection diagnosed in one ear before enrollment, with a new, unrelated ear infection in the other ear developing after enrollment, may be covered once the standard curable-condition symptom-free period has been met, since ear infections are generally treated as curable rather than a permanent structural condition. It’s worth confirming a specific insurer’s exact policy on bilateral conditions before enrolling, particularly for breeds with a well-documented risk of bilateral orthopedic issues.
How Insurers Actually Determine What’s Pre-Existing
When you file a claim — particularly your first claim, or one for a condition with any prior history — insurers typically conduct a medical record review, requesting your pet’s veterinary history to check whether symptoms of the claimed condition appear anywhere before your policy’s effective date or during the waiting period. This is exactly why maintaining complete, accurate veterinary records matters, and why switching veterinarians or having gaps in your pet’s documented history can sometimes complicate a claim, even for a condition that’s genuinely new.
Getting Insurance When Your Pet Already Has a Condition
This is a common worry, and the reassuring answer is that a pre-existing condition doesn’t disqualify your pet from getting insurance at all — it simply means that specific condition, and directly related complications, won’t be covered, while everything else about your pet remains eligible for standard coverage. A cat with a documented pre-existing kidney condition, for example, can still be insured and receive full coverage for an unrelated injury, infection, or illness — the exclusion applies narrowly to the specific pre-existing diagnosis (and, per the bilateral rule above, potentially its mirror-image counterpart), not to your pet’s insurability as a whole.
Insurers Handle This Differently — It’s Worth Comparing
Policies on curable-condition reconsideration, bilateral conditions, and symptom-free waiting thresholds genuinely vary by provider, and this is a legitimate point of comparison beyond price. Some insurers apply a 180-day symptom-free threshold for curable conditions; others require a full 12 months. Some providers explicitly distinguish between permanent and temporary pre-existing conditions in their policy language; others apply a blanket exclusion with less flexibility for reconsideration. If your pet already has a documented health history — particularly a resolved, curable issue — it’s worth asking a prospective insurer directly how they’d handle that specific condition, rather than assuming every provider treats it identically.
Practical Steps to Protect Your Pet’s Future Coverage
Keep complete, accurate veterinary records, including visits where nothing serious was found — a clean record from a normal checkup can be just as valuable as a record documenting an actual issue, since it establishes your pet’s health baseline.
Document symptom-free periods clearly if your pet had a curable condition that’s since resolved, since you may need to demonstrate that timeline to have the condition reconsidered for coverage later.
Ask specifically about bilateral condition handling before enrolling, particularly for breeds prone to joint or orthopedic issues, since this is exactly the kind of detail that doesn’t show up in a headline price comparison.
Enroll before symptoms appear whenever possible — covered in more depth in our companion guides on waiting periods and puppy insurance timing — since this remains the single most effective way to avoid pre-existing exclusions altogether.
A Side-by-Side Example
Seeing two similar scenarios play out differently makes the curable/incurable distinction more concrete. Consider two dogs, both diagnosed with a right-ear infection three months before enrolling in a policy:
Dog A has no further ear issues after treatment. Fourteen months after enrollment, they develop a new infection — this time in the left ear. Because ear infections are generally treated as curable, and because far more than the insurer’s typical 180-day symptom-free threshold has passed since the original diagnosis, this new, unrelated infection is likely to be covered under a standard policy.
Dog B is diagnosed with early-stage hip dysplasia in the right hip around the same time, before a different policy’s start date. Two years later, imaging shows dysplasia has also developed in the left hip. Because hip dysplasia is a bilateral, incurable orthopedic condition, the left-hip diagnosis is likely to be excluded as related to the pre-existing right-hip condition — regardless of how much time has passed, and even though the left hip itself showed no symptoms until well after the policy began.
Same basic pattern — a condition on one side before enrollment, a related issue on the other side afterward — but two very different coverage outcomes, driven entirely by whether the underlying condition type is classified as curable or incurable.
Frequently Asked Questions
Does a pre-existing condition mean my pet can’t get insured at all? No — it means that specific condition, and closely related complications, won’t be covered, while your pet remains eligible for standard coverage on any new, unrelated illness or injury.
Can a pre-existing condition ever become covered later? Sometimes, if it’s classified as “curable” and your pet remains symptom-free and treatment-free for the insurer’s required period — commonly 180 days to a full year. Conditions classified as chronic or incurable generally remain excluded permanently, regardless of how much time passes.
What is a bilateral condition, and why does it matter? It’s a condition that can affect either side of a paired body part (like hips, knees, or ears). If one side shows symptoms before your policy starts, many insurers will exclude that same condition type on the other side too, even if it’s never been symptomatic — an important detail that can surprise pet owners who assumed only the originally affected side was excluded.
Do I have to have a formal diagnosis for something to count as pre-existing? No — many insurers consider a symptom you or your vet simply noticed, even without an official diagnosis or vet visit at the time, sufficient to classify a later-diagnosed condition as pre-existing, if that symptom is documented as having appeared before your policy’s effective date.
How do insurers find out about a pet’s medical history? Primarily through a medical record review conducted when a claim is filed, particularly for a condition with any documented prior history — insurers typically request veterinary records covering the period before and around your policy’s start date.
Should I switch insurers if my current one won’t reconsider a resolved condition? This depends on the specific policy language of both your current and prospective insurer — some providers are more flexible about reconsidering curable conditions than others. It’s worth comparing this specific policy detail directly, rather than assuming every insurer handles a resolved condition the same way, before deciding whether switching would actually improve your pet’s coverage.
This article is provided for general informational and educational purposes only and does not constitute insurance or veterinary advice. Definitions, symptom-free thresholds, and policy handling of pre-existing and bilateral conditions vary significantly by provider and are subject to change — always verify current terms directly with the specific insurer before enrolling or filing a claim. Read our full Legal Notice, Privacy Policy, and Cookie Policy for more information.
About the Author
Miguel Ángel Cibeira researches and writes every article on The Vet Bill personally, sourcing information directly from insurance providers, NAPHIA (the North American Pet Health Insurance Association), and other verifiable industry sources. He is not a licensed insurance agent, broker, or carrier — this site offers independent research and general information, not personalized insurance advice. Read the full bio →