Financial Ombudsman Service: How to Complain

ComplaintsLast reviewed: 1 April 20257 min read

The Financial Ombudsman Service (FOS) is the UK's free, independent dispute resolution service for complaints about financial products and services. It handles over 200,000 complaints a year covering everything from bank charges and payment protection insurance to insurance claim rejections and mortgage disputes.

Key points

The FOS is free to use for consumers and small businesses — the financial firm pays a case fee.
You must complain to the firm first and receive a final response (or wait 8 weeks) before referring to FOS.
You have 6 months from the date of the firm's final response letter to refer your complaint.
FOS can award compensation of up to £415,000 for complaints about regulated activities.
FOS decisions are binding on the firm if you accept them, but you can reject a decision and go to court instead.
FOS covers banks, building societies, insurers, credit providers, investment firms, and financial advisers.

What the FOS Can and Cannot Help With

The Financial Ombudsman Service can investigate complaints about a wide range of financial products and services, provided the firm involved is authorised or regulated by the Financial Conduct Authority (FCA). This includes:

Bank accounts, savings accounts, and credit cards
Mortgages and secured loans
Personal loans and consumer credit
Car finance and hire purchase agreements
Insurance policies including home, motor, travel, and life insurance
Investments, pensions, and financial advice
Payment protection insurance (PPI)
Buy now pay later products regulated under consumer credit law

The FOS cannot help with complaints about firms that are not FCA-regulated, or with disputes about commercial policies held by larger businesses. It also cannot investigate complaints where court proceedings have already been issued, or where the complaint is primarily about the price of a product rather than the firm's conduct.

Before You Refer to FOS

You must complain directly to the financial firm before the FOS will accept your referral. Most financial firms have a dedicated complaints team and are required by FCA rules to acknowledge your complaint promptly and issue a final response within 8 weeks.

If the firm upholds your complaint in full and you are satisfied with the outcome, no further action is needed. If the firm rejects your complaint, upholds it only partially, or fails to respond within 8 weeks, you can refer the matter to the FOS.

Keep copies of all correspondence with the firm, including your original complaint, their acknowledgement, any interim letters, and their final response. The FOS will ask you to provide these documents when you submit your referral.

How to Make a Complaint to the FOS

You can refer your complaint to the FOS online, by phone (0800 023 4567), or by post. The online form is the quickest method and allows you to upload supporting documents directly.

When completing your referral, you will need to provide:

Your contact details and the firm's name
A summary of the complaint and its impact on you
The outcome you are seeking
Copies of key documents (complaint letters, the firm's final response, statements, policy documents)

The FOS will assess whether the complaint is within its remit and may ask for additional information. An investigator will then review the case and may contact both you and the firm. Many complaints are resolved at this stage through the investigator's recommendation.

The FOS Process and Possible Outcomes

The FOS investigation process typically has two stages. First, a case handler reviews the complaint and reaches a view. If both parties accept the case handler's recommendation, the complaint is resolved. If either party disagrees, the complaint is referred to an ombudsman for a formal, legally binding decision.

Outcomes that the FOS can direct include:

A refund of money lost
Compensation for financial loss or inconvenience — up to £415,000
Interest on money owed
A written apology
A change to an account or policy

If you accept the ombudsman's decision, it is binding on the financial firm. If you do not accept the decision, you are free to pursue the matter through the courts — however, this is a significant step and independent legal advice should be sought first.

Frequently asked questions

How long does the FOS take to resolve a complaint?

Timescales vary significantly. The FOS aims to resolve most cases within 3–6 months, but complex cases — particularly those involving investment or pension disputes — can take over a year. The FOS publishes its performance data on its website. You will be kept informed of progress throughout.

Can I use the FOS if my complaint is about fraud?

Yes, if the fraud involved a regulated financial product or service. For example, if you were the victim of an authorised push payment (APP) fraud and your bank failed to reimburse you under the Contingent Reimbursement Model (CRM) Code, you can complain to the FOS about the bank's decision. From October 2024, mandatory reimbursement rules apply to most APP fraud cases under PSR regulations.

Is there a time limit for bringing complaints to the FOS?

Yes. You must refer the complaint to the FOS within 6 months of the date of the firm's final response letter. There is also a general time limit of 6 years from when the problem occurred, or 3 years from when you knew (or should have known) about the problem, whichever is later. These are broad limits — the 6-month rule from the final response is the most commonly relevant one.

Do I need a solicitor to use the FOS?

No. The FOS is designed to be accessible without legal representation. The service is free to consumers and the process is straightforward. You can also get free help from Citizens Advice or a financial charity such as the Money and Pensions Service if you need assistance completing your referral.

Can businesses complain to the Financial Ombudsman Service?

Small businesses can complain to the FOS in certain circumstances. Eligible businesses include micro-enterprises (fewer than 10 employees and annual turnover or balance sheet below €2 million), small charities with annual income below £6.5 million, and small trusts. Larger businesses cannot use the FOS and must pursue their complaints through the courts or specialist commercial dispute resolution.

What if the Financial Ombudsman rules against you?

If you disagree with the final decision of an FOS ombudsman, you can reject it. Rejecting the decision means it is not binding on either party, and you remain free to pursue the matter through the courts. However, once you accept a decision, it becomes final and binding on the company. Seek independent legal advice before rejecting an FOS decision if the amounts involved are significant.

What to do next

1
Make a complaint to the Financial Ombudsman Service
Online referral form — takes around 20 minutes to complete.
2
Check if your complaint is eligible
Browse the FOS categories to confirm your complaint falls within their remit.
3
Get free financial guidance
MoneyHelper offers free, impartial guidance on financial complaints.

Official bodies and resources

Financial Ombudsman Service

Ombudsman

Resolves complaints between consumers and financial businesses such as banks, insurers, and lenders.

Visit website 0800 023 4567

Financial Conduct Authority

Regulator

Regulates financial services firms and financial markets in the UK to ensure they are honest, fair, and effective.

Visit website 0800 111 6768

Citizens Advice

Charity

Provides free, confidential, and independent advice on a wide range of issues including benefits, housing, debt, and employment.

Visit website 0800 144 8848

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Disclaimer

This information is for general guidance only and does not constitute legal advice. You should seek qualified legal help if your situation requires it.