Glossary

Pre-existing condition

An illness, injury or sign that a dog had before pet insurance began or during the waiting period, and which a policy usually will not cover.

Also called: preexisting condition, existing condition, prior condition, pet insurance exclusion

A pre-existing condition is a health problem that showed signs or was treated before a policy started, or during its waiting period. Most pet insurers exclude them for good, and a few cover a condition if the dog has been free of signs and treatment for a set time. The insurer judges this from veterinary records.

It is why many advisers suggest insuring a dog while it is young and healthy. A policy bought after a diagnosis of hip dysplasia, allergies or a heart murmur will usually not cover that condition, and sometimes related ones.

Exclusions can also reach a bilateral condition, such as a cruciate ligament tear in one knee, so ask if the other side is covered. Policy definitions differ, so read the exact wording and keep full vet records.

Last reviewed November 8, 2026

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Related terms

Pet insurance A policy that reimburses a share of veterinary bills for covered accidents and illnesses in return for a monthly premium. Waiting period The time after a pet insurance policy starts, often a few days to several months, during which some or all claims are not covered. Deductible The amount you pay toward covered vet bills before pet insurance begins to reimburse you.