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HMRC internal manual

Complaint Handling Guidance

Classifying the outcome of complaints: General

In classifying the outcome of a complaint, bear in mind that in order for a complaint to be upheld or partially upheld, we must have made a mistake (which includes unreasonable delay and poor complaints handling). Much will also depend on precisely how the complaint is articulated and the precise matter being complained about, because the classifications relate to the complaint as presented. The examples below try to demonstrate that.