Last updated: September 2026
Quick answer: Yes, most UK accident and illness policies cover cruciate ligament surgery, but with more conditions attached than almost any other claim. Many insurers apply a longer waiting period for cruciate problems, often 90 days, six months or even 12 months, and most treat the two knees as one “bilateral” condition, so a problem in one knee before cover started can exclude the other for life. With surgery costing £2,500 to £4,500 per knee, these clauses decide whether you pay £99 or £4,500.
This guide explains the wording that decides cruciate claims, what to check before you buy and what to do if a claim is refused.
The three clauses that decide a cruciate claim
1. The waiting period
Standard policies exclude illness for the first 14 days, but cruciate ligament problems often have their own, longer period. Insurers typically apply 90 days, six months, or in some cases 12 months for cruciate claims, and the exact period is in the policy schedule rather than the marketing pages. CompareMyVet reports a similar picture, with several UK insurers imposing a specific 14-day to six-month period for cruciate injuries because they are common and expensive.
Anything that appears during a waiting period is treated as pre-existing and excluded permanently.
2. The bilateral condition clause
Most insurers treat cruciate disease as affecting both knees. Waggel’s policy dictionary, for example, defines bilateral disorders as the same condition when they involve paired areas such as ears, eyes, elbows, shoulders, knees, hips and cruciate ligaments.
In practice, if your dog had any cruciate problem in one knee before the policy started, the other knee is usually excluded too. Fairer Finance notes that treatment on one leg before the policy starts typically means treatment on the second leg is not covered afterwards, even though different legs are involved, and that this is a frequent source of complaints to the Financial Ombudsman.
If both knees go after cover started, and neither showed signs beforehand, a lifetime policy will normally pay for both, subject to your annual limit.
3. Your vet fee limit
Cruciate surgery typically costs £2,500 to £4,500 per knee, and bilateral cases double that across 12 to 18 months. A £2,000 limit will not cover one knee. See how much vet fee cover you need and our full guide to cruciate ligament surgery costs.
Accident-only policies
Accident-only cover pays for injuries, not illness. Many cruciate ruptures develop gradually from degeneration rather than a single accident, so an accident-only policy may refuse the claim. If cruciate cover matters to you, you need accident and illness cover; see lifetime vs time-limited vs maximum benefit cover.
What to check before you buy
| Question to ask the insurer | Why it matters |
|---|---|
| Is there a longer waiting period for cruciate claims? | It can be up to 12 months |
| Are the two knees treated as one bilateral condition? | Decides whether the second knee is covered |
| Would a past limp or stiffness in a knee be excluded? | Vet notes count, even without a diagnosis |
| What is the annual vet fee limit, and does it reset? | One knee can cost £4,500 |
| Is physiotherapy or hydrotherapy included? | Rehab is a real part of the bill |
Ask for the answers in writing before you buy, not after your dog goes lame.
If your cruciate claim is refused
Bilateral refusals are often challenged successfully. The Financial Ombudsman Service considers the veterinary evidence and the pet’s history when deciding whether two problems are really the same condition. In one published decision, an insurer refused a claim for a dog’s right knee because the left had been treated about 18 months earlier, and the investigator upheld the owner’s complaint.
Steps to take:
- Get the refusal in writing, with the clause and the vet note it relies on.
- Ask your vet whether the two knees are clinically connected, and get that opinion in writing.
- Complain to the insurer; it has eight weeks to send a final response.
- Refer the complaint to the Financial Ombudsman Service, which is free.
Our guide to challenging a rejected claim sets out the process in detail.
Frequently asked questions
Does pet insurance cover TPLO surgery?
Yes, if the condition is covered. The technique doesn’t change the decision; the waiting period, bilateral wording and your limit do.
Will insurance cover the second knee?
If neither knee had signs before cover started, usually yes. If the first knee was a problem before the policy began, the second is often excluded.
Can I insure a dog that has already had cruciate surgery?
You can insure the dog, but cruciate problems will normally be excluded. Some insurers reconsider conditions that have been symptom-free for a set period; see pre-existing conditions.
Does switching insurer affect cruciate cover?
Yes. A new insurer will treat any previous cruciate treatment as pre-existing. Read switching pet insurance first.
Key takeaways
- Cruciate surgery is usually covered on accident and illness policies, with conditions.
- Waiting periods for cruciate claims can run to 12 months.
- Most insurers treat both knees as one condition.
- Check your limit: one knee costs £2,500 to £4,500.
Related guides
- Cruciate ligament surgery cost
- Pet insurance claim rejected? How to challenge it
- How much vet fee cover do I need?
This guide is general information, not financial advice. Always read the policy documents before you buy.