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HMRC internal manual

Complaint Handling Guidance

Avenues and time limits for making complaints: Time limits for making a complaint

In practice, the vast majority of customers make their complaint soon after the event and, where they remain unhappy with our first response, escalate matters quickly.

Although our “Complain about HMRC” section on the webpage asks customers who are unhappy with our service to let us know “as soon as possible”, we do not impose a strict deadline. While we would expect most customers to contact us shortly after the issue giving rise to the complaint occurred, there may be reasons why a particular customer was either unable to or chose not to. Rejecting a complaint because it is made too long after the event will be the exception rather than the rule, and in any case where you are contemplating taking such a line, you should first consult CCAST. Remember, if we refuse to take on a complaint and it is subsequently taken on by the Adjudicator or the Ombudsman, we will have missed the opportunity to put right any mistakes beforehand.