Postby SteLacca » Thu Jan 25, 2018 11:23 am
The legislation most often cited is the Interpretation Action 1978, s.7:
"7 References to service by post.
Where an Act authorises or requires any document to be served by post (whether the expression “serve” or the expression “give” or “send” or any other expression is used) then, unless the contrary intention appears, the service is deemed to be effected by properly addressing, pre-paying and posting a letter containing the document and, unless the contrary is proved, to have been effected at the time at which the letter would be delivered in the ordinary course of post. "
A letter returned RLS would prove the contrary for the purpose of this Act, and so the presumption of delivery cannot be made. However, if it was not returned, then this Act permits HMRC to assume successful delivery.