How do I write a formal letter or complaint?
A structure that gets a result — facts, dates, what you want, and a deadline.
- Difficulty
- beginner
- Time
- 30 min
- Read
- 2 min
Short answer
State what happened with dates, what you want, and by when. Most ineffective complaints are long on feeling and short on the specific outcome being requested, which leaves the reader nothing to act on.
The person reading your letter is deciding what to do with it, usually quickly. A letter that gives them the facts and a clear request is far easier to act on than one that expresses how you feel about it.
Step by step
- Put the reference and your details at the top.Account number, policy number, order reference, your address and contact details. Missing references are the most common cause of a slow or lost response.
- Open with one sentence saying what this is."I am writing to complain about a delivery that did not arrive on 3 March." The reader should know the subject before the second line.
- Set out the facts with dates.In order, briefly. What happened, when, who you spoke to, what was said. Bullet points or short numbered paragraphs are read; long paragraphs are skimmed.
- Leave the emotion out.Not because it is unjustified, but because it makes the letter easier to dismiss and harder to act on. Facts are more persuasive and travel better if it escalates.
- State exactly what you want.A refund of a specific amount, a repair by a specific date, an apology, a correction. "I want this sorted" gives them nothing to agree to.
- Give a reasonable deadline."Please respond within 14 days." It creates a point at which you can escalate, and it signals you intend to.
- Say what you will do next."If I do not hear by then I will refer this to the ombudsman." Factual, not threatening. It frequently changes the response.
- Keep it to one page and keep a copy.One page gets read. Attach evidence separately rather than describing it at length. Keep a copy and proof of sending.
Tips
- Email is fine for most complaints and gives you a timestamp. Use recorded delivery for anything legally significant.
- Address it to a named person or a specific department where you can. Letters to "Customer Services" get generic responses.
- If you are on the second or third attempt, say so explicitly and include the previous reference numbers. It usually moves the matter to someone more senior.
Questions people ask
What makes a complaint effective?
Specific facts with dates, and a clear statement of what you want and by when. Most ineffective complaints describe the problem thoroughly and never state the remedy sought.
Should I email or write?
Email is fine for most things and gives you a timestamped record. Use recorded delivery for anything legally significant like a notice or a formal deadline.