SAM80075 - Payments: payments overview: capital gains tax: S281 TCGA 1992 (Action Guide)
You should check the other guidance available on GOV.UK from HMRC as Brexit updates to those pages are being prioritised before manuals.
When you receive an enquiry for a statutory instalment arrangement (SIA) in accordance with Capital Gains Tax (S281 TCGA 1992) follow steps 1 - 10 below.
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1. If the request is not in writing, advise the taxpayer to submit a written request for payment by statutory instalments to the office with SA technical responsibility