Mis-sold product complaint letter (UK)

What counts as mis-selling in law

"Mis-sold" is not itself a legal term, so your letter should describe what the trader did in the words the law uses. The unfair commercial practices rules, now in Part 4 of the Digital Markets, Competition and Consumers Act 2024 for practices from 6 April 2025, prohibit misleading actions, misleading omissions and aggressive practices where they are likely to cause the average consumer to take a decision they would not otherwise have taken. The CMA's guidance says these provisions replace the old 2008 Regulations while keeping much of their scope.

Your remedies: unwind, discount, damages

The DMCC Act provides for new consumer redress rules, but on legislation.gov.uk the sections that would bring them in (232, 234 and 235) are not yet in force as at 27 September 2026. Until regulations are made, Part 4A of the 2008 Regulations continues to give you the remedies, and it now refers to the definitions in the 2024 Act. They apply where the trader engaged in a misleading action or an aggressive practice and it was a significant factor in your decision to buy.

When the problem was something left out

The Part 4A remedies do not cover misleading omissions. If your complaint is that something important was not mentioned, the Consumer Rights Act 2015 is often the stronger footing. For services, section 50 makes anything the trader said or wrote to you about the trader or the service a term of the contract if you took it into account when deciding to buy. For goods, section 11 says they must match their description, and key information the trader gave you about their main characteristics becomes part of the contract. Where that term is broken, you have the Consumer Rights Act remedies: for goods, rejection, repair or replacement, or a price reduction; for services, repeat performance or a price reduction, and where what was said was about the trader rather than the service, a price reduction.

Financial products: a separate route

Insurance, loans, credit, investments and other financial products are usually complained about to the firm first and then to the Financial Ombudsman Service, which is free. The firm normally has up to 8 weeks to send a final response. If it does not, or you disagree with it, you can take the complaint to the Ombudsman, and you need to do so within 6 months of the date of the final response. The Ombudsman also says you usually need to complain to the business within 6 years of the problem, or 3 years of when you became aware of it, though exceptional circumstances can be considered.

Evidence makes or breaks a mis-selling complaint

Mis-selling usually happens in a conversation, and the trader will remember it differently. Gather what you can: the advert or product page (a screenshot, or an archived copy if it has changed), the brochure, the contract, any sales emails or chat logs, and a dated note of what was said and by whom, written as soon as possible. Put the claim and the reality next to each other in the letter so the reader cannot miss the gap.

Mis-sold product complaint letter

Edit this template with your facts, dates, and requested outcome before sending.

Subject: Formal complaint — mis-sold [product/service], [order or contract reference]

Dear [Company] complaints team,

On [date] I bought [product/service] from you for [amount], reference [reference], [in store at [location] / by phone / online].

What I was told: [the exact statement, and who made it — for example, "the sales adviser, [name], told me the policy covered accidental damage including liquid spills" / the product page stated "[quote]"]. [Attach the advert, screenshot, brochure or note of the call.]

What I actually got: [how the product or service differs — for example, the policy terms exclude liquid damage, which was not mentioned].

This statement was a significant factor in my decision to buy. I would not have bought [or: would not have paid this price] had I known the true position.

I am asking you to [choose one]:
- accept that I am unwinding the contract and refund the [amount] I paid. I am rejecting the product within 90 days of [the contract / delivery / the service starting]; or
- refund [percentage or amount] of the price as a discount; and
- reimburse my resulting losses of [amount], namely [itemise].

Please respond within 14 days. If this is not resolved I will consider [the relevant ADR scheme / my card provider / the Financial Ombudsman Service].

Yours sincerely,
[Your name]
[Address]
[Reference]

Common mistakes to avoid

• ✕Saying "I was mis-sold" without quoting what was actually said or shown
• ✕Waiting beyond 90 days to reject the product, when unwinding was the remedy you wanted
• ✕Relying on the old 2008 Regulations for the unfair-practice rules, which the 2024 Act replaced from 6 April 2025
• ✕Claiming the Part 4A remedies for something that was left out, rather than using the Consumer Rights Act
• ✕Not explaining why the statement mattered to your decision to buy
• ✕For a financial product, missing the 6-month window to refer the final response to the Financial Ombudsman Service

Next steps

1. 1Write down exactly what you were told or shown, by whom and when
2. 2Save the advert, product page, contract and any messages
3. 3Check whether you are still within 90 days if you want to unwind
4. 4Send the complaint stating the remedy you want and a reply date
5. 5For a financial product, keep the final response and note the 6-month Ombudsman deadline
6. 6Otherwise, check whether the trader belongs to an ADR scheme, or use your card provider