A well-organised formal complaint letter can make it easier for a business, landlord, employer, bank or public service to understand what went wrong and what you want done. This guide provides a reusable UK complaint letter template, an evidence checklist and practical escalation steps, while highlighting the deadlines and route differences that can affect your options.
Overview
A complaint letter is more effective when it is treated as a clear record of events rather than an emotional account. Your aim is to explain the problem, identify the relevant agreement or service, show the evidence, and request a realistic remedy.
Before writing, decide what outcome you want. Depending on the situation, this might be a repair, replacement, refund, correction of records, compensation for a direct loss, an explanation, or a review by a more senior person. You may have several possible remedies, but avoid asking for outcomes that do not relate to the actual problem.
Keep the complaint factual and specific. State dates, reference numbers, amounts and names where known. If you rely on legal rights, describe the principle carefully rather than filling the letter with legal language. For example, a consumer might refer to rights concerning goods or services under the Consumer Rights Act 2015, but the correct remedy can depend on the facts, timing and type of contract. Our Consumer Rights Act UK guide provides further background.
A formal complaint is not always the same as a legal claim. It usually gives the recipient an opportunity to investigate and resolve the issue. It can also create a useful paper trail if you later need to use an ombudsman, regulator, payment dispute process or court procedure.
Reusable formal complaint letter template
Subject: Formal complaint about [product, service, tenancy, transaction or decision] – [reference number]
Dear [name or complaints team],
I am writing to make a formal complaint about [brief description of the problem]. The relevant account, order, policy, tenancy or case reference is [reference].
The key events are:
- On [date], [explain what happened].
- On [date], I contacted [person or organisation] and was told [briefly state the response].
- On [date], [explain any further failure, loss or consequence].
I believe this requires investigation because [explain the service failure, contractual problem, inaccurate decision, missed repair, data issue or other concern]. I have attached or linked the relevant evidence, listed below.
To resolve the complaint, I ask you to [state the remedy clearly]. Please also confirm [any explanation, correction, timescale or action you need].
Please acknowledge this complaint and provide a substantive response within a reasonable period, or tell me when I should expect one. If you do not resolve the matter, please explain your final position and the next stage of your complaints procedure.
Yours faithfully,
[full name]
[address or account details if appropriate]
[email and telephone number]
Adapt the wording to the situation. Do not describe a message as a “letter before action” unless you genuinely intend it to be a formal pre-action step and have checked the applicable court guidance or protocol.
Checklist by scenario
Consumer goods, services and refund disputes
- Identify the seller, provider, order number and purchase date.
- Describe the fault, delay, cancellation or service not provided.
- Explain whether you want a repair, replacement, repeat performance, price reduction or refund.
- Attach the receipt, order confirmation, photographs, messages and relevant terms.
- Record any reasonable direct loss, such as an additional cost caused by the problem, and explain how it was calculated.
- Ask the business to confirm its proposed remedy and timescale.
If the business does not resolve a card purchase dispute, check whether a payment-provider route may apply. A car dealer complaint or a dispute about building work may involve additional facts and remedies, so avoid copying a general consumer letter without adapting it.
Banks, insurers, broadband and other regulated services
- Use the provider’s published complaints channel where possible.
- Include the policy, account or service reference and the dates of earlier contact.
- Explain the financial impact, but distinguish proven losses from inconvenience or disappointment.
- Ask for a final response if the issue remains unresolved.
- Keep the provider’s acknowledgement and any information about referral to an ombudsman.
An ombudsman complaint normally follows the organisation’s internal process, although the precise route and eligibility depend on the sector. Do not assume that every regulator investigates individual complaints or awards compensation.
Landlord, letting agent and housing complaints
- State the property address, tenancy reference and the dates problems were reported.
- Describe the repair, damp, mould, safety, harassment or deposit issue precisely.
- Include photographs, inspection reports, contractor appointments and copies of previous reports.
- Explain any immediate risk and ask for a written plan with dates.
- Keep records of access arrangements and whether appointments were missed.
Routes differ between a private landlord, letting agent, council or housing association. See the guides on landlord complaints, letting agent complaints and council housing complaints. Deposit disputes may need to use the relevant tenancy deposit scheme rather than a general complaints team.
Employment grievances and workplace disputes
- Check the employer’s grievance policy and submit the grievance through the stated channel.
- Set out the conduct, decision or treatment complained about, with dates and witnesses where relevant.
- Explain the effect on you and identify the outcome sought.
- Keep meeting invitations, notes, emails, policies and supporting documents.
- Check time limits separately if you may need advice about an employment tribunal.
A workplace grievance is not necessarily the same as a claim for unfair dismissal, discrimination or unpaid wages. For unpaid wages and holiday pay issues, keep a separate calculation of the amount owed. For certain employment disputes, contacting ACAS may be time-sensitive; read the ACAS Early Conciliation guide before assuming that an internal complaint stops any legal deadline.
Privacy and data complaints
- Identify the personal data, account or processing activity concerned.
- State whether you want access, correction, deletion, restriction, an explanation or another response.
- Attach earlier correspondence and quote the relevant request or case reference.
- Avoid including unnecessary sensitive information in an ordinary email.
- Keep a copy of the organisation’s response before considering a complaint to the data protection regulator.
A subject access request and a complaint about misuse of personal data are different types of communication. Label the request clearly so the organisation can understand what you are asking it to do.
What to double-check before sending
- The correct recipient: Use the organisation’s complaints address, online form or designated officer. Sending a complaint to a general inbox may delay it.
- Your chronology: Put events in date order and separate what you know from what you believe or have been told.
- Your remedy: Ask for a defined result. “Please sort this out” is less useful than “Please arrange the repair and confirm the appointment date.”
- Your evidence: Number attachments and refer to them in the letter, for example, “Attachment 2: photographs dated 14 March”.
- Confidentiality: Remove unrelated personal information belonging to other people and use secure upload facilities where available.
- Deadlines: Check the contract, complaints procedure and any applicable legal limitation period. A complaint does not automatically extend every court or tribunal deadline.
- Delivery: Save the sent email, submission confirmation or proof of posting. If posting matters, consider a delivery method that gives you evidence of receipt.
Set a reminder for the response date. If there is no reply, send a short follow-up quoting the original date and asking for confirmation that the complaint has been logged. Avoid restarting the story from scratch each time.
Common mistakes
- Using an aggressive tone: Threats and insults can obscure the issue. Firm, factual wording is usually easier to investigate.
- Sending too much evidence: A large unlabelled file can make important information difficult to find. Send the documents that prove the key points first.
- Making unsupported accusations: Describe the conduct and its effect instead of alleging dishonesty or criminality without evidence.
- Accepting a verbal promise: Ask for the proposed remedy, date and any conditions in writing.
- Relying on social media first: Public posts rarely replace the organisation’s formal process and may expose personal information.
- Confusing a regulator with a compensation route: Some regulators record intelligence or supervise organisations but do not decide individual refunds.
- Missing a separate legal deadline: Escalating a complaint can be sensible, but it should not be treated as a substitute for checking limitation or tribunal rules.
If informal contact has failed, the next step may be an internal final review, an ombudsman, a regulator, a payment dispute such as a card claim, or a civil claim. A builder complaint or a tenancy dispute may require a different evidence set and pre-action approach. Before starting a small claim, calculate the amount, identify the correct defendant, check the relevant procedure and consider whether a letter before action is appropriate.
When to revisit this checklist
Return to this guide whenever the underlying dispute changes: a business issues a final response, a repair is missed, new evidence appears, a payment provider rejects a claim, or you are considering an ombudsman or court route. Recheck the recipient’s current complaints procedure rather than relying on an old address or form.
It is also sensible to revisit the checklist before seasonal purchasing periods, moving home, renewing insurance or signing a new service contract. Keep a simple complaint file containing the original agreement, chronology, evidence, sent messages, responses and deadline reminders.
Your practical next step is to write a one-page chronology, choose the remedy you want, attach only the key evidence and send the complaint through the correct channel. If the matter involves substantial money, housing safety, employment rights, discrimination, data misuse or an approaching deadline, consider obtaining independent legal or specialist advice rather than relying only on a general template.
