Money & Budgeting

How to Complain to the Financial Ombudsman — Step by Step

Complete guide to making a complaint to the Financial Ombudsman Service (FOS) in the UK. Covers when to complain, how the process works, timelines, and what outcomes to expect.

By PocketWise · · 5 min read

If you have a dispute with a bank, insurer, or financial firm and they will not resolve it, the Financial Ombudsman Service (FOS) can investigate and make a binding decision. Here is how the process works.

When to Use the Financial Ombudsman

Use the FOS for complaints about Do NOT use the FOS for
Banks and building societies HMRC (use tax tribunal)
Credit card and loan companies DWP / benefit decisions (use mandatory reconsideration, then tribunal)
Insurance companies Accountants (unless FCA-regulated)
Mortgage lenders and brokers Employers (use employment tribunal)
Financial advisers (FCA-regulated) Solicitors (use Legal Ombudsman)
Investment and pension firms Energy companies (use Energy Ombudsman)
Money transfer services Telecoms (use Ofcom/CISAS)
Debt collectors NHS (use Parliamentary and Health Service Ombudsman)
Payday lenders Unregulated cryptocurrency firms

Step-by-Step Complaint Process

Step 1: Complain to the Financial Business First

Detail Information
This is required You MUST complain to the firm first — the FOS will not investigate until you have
How to complain In writing (email or letter) — keep a copy
What to include What happened, what went wrong, what you want them to do about it
Their deadline They must give a final response within 8 weeks
If they do not respond in 8 weeks You can go straight to the FOS
If they refuse your complaint You receive a “final response letter” — you can then complain to the FOS

Step 2: Receive the Final Response Letter

Outcome Your next step
Firm upholds your complaint and offers fair resolution Accept — complaint resolved
Firm offers a partial resolution Consider whether to accept or escalate to FOS
Firm rejects your complaint You have 6 months to refer to the FOS
No response within 8 weeks Refer to the FOS immediately

Step 3: Submit Your Complaint to the FOS

Method Details
Online financial-ombudsman.org.uk — quickest method
Phone 0800 023 4567 (free), 0300 123 9123
Post Financial Ombudsman Service, Exchange Tower, London E14 9SR
What to include Your details, the firm’s details, what happened, what you want, copies of key correspondence
Time limit Within 6 months of the firm’s final response letter

Step 4: FOS Investigation

Stage What happens
Acknowledgement FOS confirms receipt and assigns your case
Information gathering FOS requests documents from you and the firm
Assessment by caseworker An adjudicator reviews the evidence and gives an initial opinion
Initial opinion If you accept — case resolved. If not — request an Ombudsman’s decision
Ombudsman’s decision A senior Ombudsman reviews the case and makes a final, binding decision

What the FOS Can Award

Award type Typical range
Refund of charges/fees Full amount incorrectly charged
Compensation for financial loss Up to £430,000 (complaints from April 2024+)
Interest on money owed 8% simple interest per year (standard)
Compensation for distress and inconvenience £100–£500 (moderate), £500–£2,000 (significant), £2,000+ (severe)
Direction to correct a mistake e.g. correct a credit file, reinstate a policy
Apology Can recommend but not enforce

Compensation Limits

When the complaint occurred Maximum award
From 1 April 2024 £430,000
1 April 2023 to 31 March 2024 £415,000
1 April 2019 to 31 March 2023 £375,000
Before 1 April 2019 £170,000

Common Types of FOS Complaint

Complaint type What the FOS considers
PPI mis-selling (legacy) Whether you were sold PPI you did not need or want
Bank charges or unfair fees Whether charges were applied fairly and in accordance with terms
Insurance claim rejection Whether the rejection was fair based on the policy terms
Mortgage advice Whether advice was suitable for your circumstances
Investment losses from poor advice Whether the adviser recommended suitable investments for your risk profile
Fraud and unauthorised transactions Whether the bank should have prevented the fraud or reimbursed you
Delayed or denied pension transfer Whether the firm handled your pension transfer promptly and fairly
Unaffordable lending Whether the lender properly assessed your ability to repay
Credit file errors Whether the firm reported accurate information

Tips for a Successful Complaint

Tip Details
Keep all evidence Emails, letters, call recordings, screenshots, statements
Note dates and times When you spoke to the firm, who you spoke to, what was said
Be specific about what happened Facts and chronology matter more than emotion
State what you want Be clear about the outcome you are seeking
Explain the impact How were you affected financially or emotionally?
Respond promptly to FOS requests Delays on your side slow the process
Be honest Inaccuracies undermine your credibility
Include a timeline Especially helpful for complex complaints

What to Include in Your FOS Complaint

Essential information Details
Your full name, address, date of birth For identification
The firm’s name Who you are complaining about
Account or policy number Helps the firm locate your records
Timeline of events What happened and when
How the firm responded to your complaint Include their final response letter
Evidence supporting your complaint Correspondence, statements, screenshots
What you want Refund, compensation, correction to your account, etc.
The impact on you Financial loss, stress, inconvenience

Timeline

Stage Typical duration
Complain to firm Allow 8 weeks for their response
Refer to FOS Must be within 6 months of final response
FOS acknowledgement 1–2 weeks
FOS investigation 3–12 months (varies widely)
Adjudicator’s opinion Part of investigation
Ombudsman’s final decision (if requested) Additional 3–6 months
Payment of compensation (if awarded) Within 28 days of accepting the decision

If You Disagree with the FOS Decision

Option Details
Accept the adjudicator’s opinion Case resolved — firm must comply
Reject and request Ombudsman’s decision A senior Ombudsman reviews from scratch
Accept the Ombudsman’s decision Legally binding on the firm — you receive what was awarded
Reject the Ombudsman’s decision Decision does not bind you — you can pursue other options (e.g. court)
Take legal action instead You can sue the firm in court, but cannot usually do both

The Ombudsman’s decision is final for the financial firm — they cannot appeal. If you accept it, they must pay. If you reject it, you keep your right to go to court but the FOS decision carries weight.

Related guides:

Sources

  1. MoneyHelper — Everyday money