Pre-Existing Conditions and Pet Insurance: What Counts and Why

A pre-existing condition is any illness or injury your dog showed signs of, was examined for, or was treated for before the insurance policy started, or during its waiting period. Most dog insurance policies exclude them. Some will cover a condition that was fully cured and has stayed symptom-free for a set time; chronic conditions are usually excluded permanently.

This is the single most common reason dog insurance claims are refused, and the definition is wider than most owners expect.

What counts as a pre-existing condition

Definitions vary by insurer and country, but they usually share three triggers. Spot’s published US disclosure is a clear example. It treats a condition as pre-existing if, before the policy’s start date:

1. a vet gave medical advice about it,
2. your dog received treatment for it, or
3. records or other verifiable sources show your dog had signs or symptoms of it.

Note the third point. A diagnosis is not required. A vet’s note saying “owner reports occasional limping, right hind” can be enough to exclude a later cruciate claim on that leg.

Australian insurers often go further. Finder describes a “reasonable person” test some use: if a reasonable owner would have noticed a problem, it can count even if you never took your dog to the vet for it.

Most policies also count anything that starts during the waiting period as pre-existing. Which? and Spot’s disclosure both say so. So a dog that develops diarrhoea on day 9 of a 14-day illness waiting period may have that condition excluded for good.

Curable versus incurable conditions

This is where insurers draw the most important line.

Curable (also called temporary or historic): a problem that resolves fully. Examples include a broken bone that has healed, a one-off ear infection or a bout of gastroenteritis. The NAIC says curable pre-existing conditions may be covered after a waiting period. Which? describes these as historic conditions.

Incurable (chronic): a problem that can be managed but not cured. The NAIC gives diabetes and cancer as examples; Which? lists heart conditions and hip dysplasia. Spot’s disclosure defines a chronic condition as one that can be treated or managed, but not cured. These are usually excluded for the life of the policy, or covered only on a limited basis.

The grey area is recurring problems. Skin allergies and ear infections that flare every summer are often treated as a single, ongoing condition, not a series of curable ones. If your dog has had the same problem more than once, assume an insurer will see it as chronic until it tells you otherwise in writing.

Related conditions are usually excluded too. Finder gives the example of cataracts that develop because of excluded diabetes.

Symptom-free periods and look-back rules

“Look-back” is used in two ways in pet insurance, and both matter.

1. How far back the insurer looks in your dog’s records. When you make your first claim, most insurers ask for your dog’s full vet history, sometimes from the breeder or rescue too. They read it for any earlier sign of the problem you are claiming for. There is often no fixed cut-off: a note from puppyhood can count.

2. How long a cured condition must stay quiet before it can be covered. Insurers that cover curable pre-existing conditions usually require a period with no signs, treatment or advice:

Finder notes that in Australia the symptom-free period often has to be served either while the policy is active or immediately before the claim. Read your policy’s exact wording.

Bilateral conditions: the “other leg” problem

A bilateral condition is one that can affect both sides of the body: both knees, both hips, both elbows, both eyes, both ears. Many insurers treat it as one condition, whichever side shows it first.

Animal Friends, a UK insurer, spells out how this works on its policies: if a bilateral condition existed before cover started or during the waiting period, both sides are excluded. It also treats both sides as one condition for the vet fee limit, so a claim for the left knee reduces what is left for the right.

CHOICE’s buying guide (last updated in 2021) gives the same example from Australia: a cruciate injury in one leg means the other leg will not be covered either. Finder adds that some Australian policies say cruciate ligament conditions can never count as temporary, however long the dog has been sound. The CCPC in Ireland also warns that some policies restrict bilateral cover.

Insurers have a reason. In a 2014 study in the Canadian Veterinary Journal that followed dogs for three years, about four in ten went on to rupture the second cruciate ligament after the first, and around a fifth already had both knees affected when first seen. If your dog has ever limped on a back leg, assume both knees may be excluded until you see the insurer’s answer in writing.

How to avoid getting caught out

You cannot erase history, but you can avoid surprises.

1. Get your dog’s full vet records before you buy. Read them for anything that could be read as a symptom, including passing comments.
2. Ask the insurer to list exclusions up front. Some insurers will review your dog’s history before your first claim. Finder suggests asking for a pre-existing condition assessment during the cooling-off period, while you can still cancel.
3. Ask about bilateral conditions specifically. Search the policy wording for “bilateral”, “temporary condition” and any named exclusions for knees or ligaments.
4. Note the waiting period dates. Avoid starting a policy right before something risky, and know when cover for illness and orthopaedic problems actually begins.
5. Be honest on the application. Non-disclosure can void a claim or the whole policy.
6. Think hard before switching. A new insurer will normally treat anything your current one is covering as pre-existing. The NAIC also warns that some US insurers may treat a condition treated during one policy term as pre-existing at renewal, so check renewal terms. Some US states now prevent this: Spot’s Delaware disclosure, for example, says a condition covered in a previous policy period is not treated as pre-existing at renewal if there was no break in cover. Delaware is one of 17 states that the NAIC, as of summer 2026, lists as having adopted its Pet Insurance Model Act (New Jersey’s version starts on 1 January 2027), so ask the insurer how the rules work in your state.

See a vet now if: your dog is limping and won’t bear weight, has repeated vomiting or diarrhoea, is drinking or urinating much more than usual, or has a lump that is growing. Never delay a vet visit to keep the record clean. Insurers can still treat signs you should have noticed as pre-existing, and a delayed diagnosis usually costs your dog more than it saves you.

Why insuring young makes such a difference

Every vet visit adds to the record an insurer will read. A puppy insured at eight weeks has almost nothing on file, so almost nothing can be excluded. The same dog insured at four, after two ear infections, a bout of colitis and a limp, may start with a list of exclusions that covers its most likely future claims.

Age also brings other restrictions. The CCPC says some Irish insurers will not accept new pets over six to eight, and some breeds only up to five. Which? says insurers typically add higher excesses or co-payments for older pets, with dogs over about eight generally treated as older.

There is a waiting period to serve whenever you start, so insuring the day you bring a puppy home, or as soon as the policy allows, gives you the cleanest start. Policies set a minimum age for new puppies, so check yours.

If your dog already has a pre-existing condition

You still have choices:

• Look for insurers that cover cured conditions after a symptom-free period, if the condition was genuinely temporary.
• Accept the exclusion and insure everything else. A policy that excludes your dog’s allergies still covers a swallowed sock or a broken leg.
• Build a dedicated fund for the excluded condition and ask your vet about payment plans for ongoing treatment. Finder suggests both for chronic conditions that are excluded.
• In the UK, check whether you qualify for means-tested help from PDSA, Blue Cross or the RSPCA, as Which? suggests for owners who cannot afford insurance.

The bottom line

Insurers exclude anything your dog showed signs of before cover began, and many count both sides of the body as one condition. Curable problems can sometimes be covered after a symptom-free period; chronic ones usually cannot. The most effective protection is simple: insure your dog young, before the record fills up, and get any exclusions in writing before you rely on the policy.