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HMRC internal manual

Inheritance Tax Manual

Communications: British Document Exchange: what is British Document Exchange?

British Document Exchange (otherwise called ‘Britdoc’ or ‘DX’) is an alternative to the Royal Mail for sending business letters to agents. It is a licensed private postal system whose membership includes many solicitors and accountants and some Government departments.

It was used for many years by HMRC for Inheritance Tax written correspondence.  However, since 1 April 2016, we no longer use this service.