UK Financial Ombudsman Health Insurance Complaints: A Complete Guide

What Is the Financial Ombudsman Service?

The Financial Ombudsman Service (FOS) is a statutory body created by Parliament to resolve disputes between consumers and financial services firms — including insurers. It is entirely free for consumers, funded by the financial services industry, and its decisions are legally binding on insurers.

For private medical insurance (PMI) holders in the UK, the FOS is the single most powerful recourse available when an insurer mishandles a claim or unfairly applies a policy exclusion.

What Types of PMI Disputes Can the FOS Handle?

• Denied claims for treatment or specialist consultations
• Pre-existing condition exclusions applied incorrectly
• Moratorium exclusion disputes
• Policy cancellation or non-renewal complaints
• Disputes over what counts as "medically necessary" under UK PMI policies
• Claims handling delays and poor service

Before You Go to the FOS

You must first exhaust the insurer's internal complaints process. Under FCA rules, the insurer must:

• Acknowledge your complaint within 5 business days
• Issue a final response within 8 weeks
• Explain your right to refer to the FOS in the final response letter

Keep copies of all correspondence. You will need these for the FOS submission.

How to Submit a FOS Complaint

1. Visit financial-ombudsman.org.uk and complete the online complaint form
2. Attach your insurer's final response letter (or note that 8 weeks have passed without a response)
3. Provide all relevant documentation: your policy, the claim, the denial letter, clinical notes, and your correspondence with the insurer
4. Complete the FOS's own summary of the dispute

You have 6 months from the date of the insurer's final response letter to submit to the FOS.

What Happens After Submission?

The FOS assigns an adjudicator who reviews both sides of the dispute. The adjudicator may ask for additional information and will normally issue an initial assessment — typically within 90 days for straightforward cases, longer for complex disputes. Either party can accept or reject the adjudicator's view. If rejected, the case goes to an Ombudsman who issues a final, binding decision.

Success Rates and What They Mean for You

In 2024/25, the FOS upheld approximately 35–45% of insurance complaints in consumers' favour (the specific rate varies by product type and insurer). For PMI disputes involving medical necessity or pre-existing conditions, the rate is higher for well-documented cases.

The most significant factor in FOS success is the quality of the clinical argument. Cases supported by physician-authored documentation that directly addresses the insurer's denial reasoning are disproportionately successful.

Frequently Asked Questions

Does using the FOS affect my insurance policy?

No. FCA rules prohibit insurers from penalising policyholders for making legitimate complaints.

Do I need a solicitor to use the FOS?

No. The FOS is designed to be used directly by consumers without professional representation. However, a professionally written complaint with strong clinical support significantly improves your position.