# How to reply to a letter you don't understand > A four part reply that works for a council notice, an insurance letter, or a bill you think is wrong. What to ask, what to leave out, and when to call. Canonical: https://dev.swirlai.app/blog/how-to-reply-to-a-letter-you-dont-understand Last updated: 2026-10-31 Write down three things first: who sent it, what they want, and the date. Then reply in four parts. Say what you understood, ask them to confirm the parts you are unsure about, say what you are doing next, and give a date. Keep it to one page. Do not apologise for not understanding it, and do not guess at a number. You do not have to understand a letter to answer it. You have to be clear about what you are answering and what you are asking back. Those are two different skills, and the second one is easier. ## The four parts - What you understood: one sentence, in your words. If you have it wrong, this is where they correct you. - What you are asking them to confirm: the amount, the date, the reference, or which of two letters they mean. - What you are doing next: sending a document, making a payment, or waiting for their answer. - By when: a date. It gives the letter a shape and makes a reply likely. That structure works for a council tax notice, an insurance decision, a bill you think is wrong, and a letter from a school. The words change. The shape does not. ## What to leave out Leave out the story. Leave out why you are behind, unless you are asking for something because of it. Leave out apologies for not understanding the letter, because that is not a fact they need. Leave out any number you are not sure of. If you guess at an amount and you are wrong, you have created a new problem in writing. ## The one line that does the work Please confirm in writing whether the amount of 740 pounds and the date of 14 November are correct, so I can respond accurately. That sentence is polite, it is specific, and it puts the uncertainty back on the sender, which is where it belongs. ## When to stop writing and call Call when the letter mentions a court, a tribunal, bailiffs, or a deadline inside seven days. Call when the amount is large enough that being wrong matters. Call when you have sent two letters and had no answer. Then write down the date, the name of the person, and what they told you. A note of a phone call is evidence. A memory of one is not. ## Keep the copy Keep what you sent and what they sent back, in one place, with the dates. If the same question comes back in three months, the file answers it in seconds. That is the whole reason to keep a case rather than a memory of one. ## Do this in Swirl You do not have to understand it to answer it. **A normal chat:** A normal chat offers an apology and a vague paragraph. Swirl writes four parts that put the uncertainty back on the sender. [Read the fair comparison](https://dev.swirlai.app/vs/chatgpt) Prompt: I do not understand this letter. Write me a one page reply that says what I understood, asks them to confirm the amount and the date, and gives a date I will respond by: [Try this in Swirl](https://dev.swirlai.app/?for=writing&utm_source=blog&utm_medium=how-to-reply-to-a-letter-you-dont-understand) ### Should I reply by email or by post? Reply in whatever channel they used, unless the letter says otherwise. Email is faster and gives you a dated copy. If the letter came by post and mentions a formal process, send a copy by post as well. ### What if I do not know the reference number? Say so, and describe the letter instead: the sender, the date on it, and the amount. Ask them to confirm the reference in their reply. A missing reference is not a reason to delay the reply. ### Can I ask someone else to reply for me? Yes, if you give them written permission, and many organisations require that in writing before they will discuss the account. A short letter of authorisation signed and dated is usually enough. ## Related - [What happens if I ignore a letter?](https://dev.swirlai.app/blog/what-happens-if-i-ignore-a-letter) - [What to do about a letter you cannot pay](https://dev.swirlai.app/blog/what-to-do-about-a-letter-you-cannot-pay) - [How to explain a letter in plain English](https://dev.swirlai.app/blog/how-to-explain-a-letter)