Brexit changes mean people will soon have to fill in customs declarations for all goods being sent further than the UK.
The changes come in on January 1 and the Isle of Man Post Office says any goods sent to international destinations need accurate customs documents, either electronically or on paper.
It'll include information about the sender, recipient and contents.
Geoff Rickard of the Post office says in the past declaration forms were needed to for countries beyond Europe, but after Brexit all European countries will need them too - otherwise mail could be delayed or returned.
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