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HMRC internal manual

Inheritance Tax Manual

Non-statutory assurances and other types of certificate: non-statutory assurances on taxpaying settlement cases

Whenever you close a settlement file, or you have no enquiries to raise based on the account delivered by the taxpayer, you should issue an SL135 closure letter.

Select the relevant options, making sure that the letter is correctly headed to reflect the title at which you are issuing the letter. The letter includes a unique code which enables us to check that the letter is genuine and reassures the taxpayer that the letter is valid. There is no need to sign or stamp the letter.