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HMRC internal manual

Technical Teams Operational Guidance

Case closure: reopening settlements: principles

Where there has been a negotiated agreement resulting in a contract entered into in good faith by both sides the Courts would be unlikely to hear sympathetically any applications to vary the agreement simply because one side or the other wished to re-consider. Investigators should always stress at the settlement meeting that the offer once accepted by the Board is final so long as the taxpayer has not misled HMRC during it’s enquiries.

Where the settlement is not by way of a contract offer the normal rules of finality and the error or mistake provisions apply.

SI do not usually get immediately involved if a taxpayer has problems meeting the terms of the settlement (TTOG6415). The taxpayer should be referred to the Network Unit and Enforcement Office and it is important that SI do not compromise their position. Enforcement office may seek SI advice. SI should assist as far as possible and seek further advice from the SI Insolvency Section where required.