The deadline for UK drone pilots to register their details with the Civil Aviation Authority (CAA) is by the end of today (29 November).
Registration applies to anyone with a drone which weighs more than 250g (8.8oz), failure to register will result in a £1,000 fine.
The drone operator must be over 18 and pay a £9 annual fee.
Estimates by the CAA are that there are 130,000 drone users in Britain, but so far only around 50,000 people have registered.
In December, Gatwick Airport was closed after the airport received reports of two drones flying over its airfield, prompting its immediate closure.
In addition to the fine, users with unregistered drones also potentially face criminal charges if they fly them illegally or negligently, according to the police.