Understand it, check it, keep it.
HMRC tax letters, explained.
Understand any letter, check their figures, and keep it all in one place.
Around 1.8 million Simple Assessment letters are going out this cycle, and HMRC's own guidance says to check the figures against your records before paying. Every letter here ends one of three ways: some need no reply at all, some need an answer by a date, and some are worth professional help. We say which, plainly.
Check my Simple Assessment I got a different letter
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First, three letters that should skip this site
Almost everything here can be handled calmly. Three things change that. If your letter mentions Code of Practice 9 or the Contractual Disclosure Facility, or comes from the Fraud Investigation Service, HMRC suspects serious wrongdoing and the protections on offer have strict rules: speak to a specialist before you respond. If it is a penalty, an assessment, or says a check has started, the deadline may be fixed by law: read this today. None of these? Carry on below.
Start where you are
Pick the closest. You can change your answer at any point, and "not sure" is a normal answer.
- Check a Simple AssessmentThe PA302 letter that says how much HMRC thinks you owe. Compare its figures against your own records, line by line.
- Understand any HMRC letterPaste it and get a plain-English identification: which campaign, what it asks, what the deadline really means.
- Not sure it's really HMRC?Check the scam signs first, using GOV.UK's own lists. Some genuine HMRC contact arrives by text, so neither instinct is enough.
Helping someone? Checking a parent's letter, together or from afar, works the same. Tell us it's for them when the check asks whose letter it is, and their check stays separate from anything of yours.
How a check works
- What the letter says. You copy in the figures the letter printed: income, pension, savings interest, tax paid, the amount HMRC asks for.
- What your documents say. The same lines from your P60, pension statements and bank interest certificates.
- The comparison. Tax Letters compares each line and says one of three things: matched, differs (with the difference), or couldn't check. No verdicts, no drama.
- What happens next is yours. If a figure differs, you have 60 days from the letter's date to put it to HMRC, a window set by law, and Tax Letters works out your exact date. If everything matches, you can pay knowing you checked.
The 60-day rule: Taxes Management Act 1970, section 31AA. The letter volumes: GOV.UK press release, 28 Jul 2026.
No scare tactics. No "amnesty" talk. No promises.
You will never get
- Countdown pressure or frightening language
- Promises about outcomes, refunds or penalties
- Advice pretending to know your situation
- Advertising trackers on any page
You will always get
- The arithmetic done properly, in your browser
- What each deadline means in law, honestly
- Dated sources, and a route to qualified help
- A service designed to know as little about you as possible
How HMRC letter deadlines actually work · Who runs Tax Letters and how it is funded · Privacy
After your check, Tax Letters stays quiet
Most tax services want your attention. Tax Letters is built the other way round: it decides what deserves your attention, and most of the time the answer is nothing. Tax Letters Watch is being built to follow HMRC's campaigns, rule changes and scam waves for you, and it will speak up only when something actually applies to you. It is not live yet, and this site will say so plainly when it is.