Normally, half-a-million British citizens visit Malta every year.
However, it is believed that about 20,000 Brits are on the island right now.
It is unlikely that those abroad in Malta will be able to change their flights to get home before the deadline since the announcement was made 30 hours before the measure takes effect.
Returning from Malta after 4am on Saturday means you will need to stay at home for 14 days.
Those in quarantine will only be able to leave home for medical assistance, to attend court or a funeral, or to go shopping for essentials if there is no one else who can do this for them.
Anyone who breaks these rules will be charged £1,000, or £480 in Scotland.