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HMRC internal manual

Specialist Investigations Operational Guidance

Information and inspection powers: Schedule 36 FA 2008: opportunity letters and informal requests

Where appropriate you may seek information informally before using your statutory powers. There is no objection to combining an informal request with an opportunity letter, which is the first stage of the formal process. It is a matter of judgement whether an informal approach without any reference to statute is more likely to succeed, or whether it is better to save time by taking both steps together.