You can buy a private (personalised) number plate for your vehicle from DVLA or from a private dealer.
Take a private number off (‘retention’)
If you don’t want to use your private number anymore you can apply to take it off your vehicle, You can hold on to it until you want to use it again in the future - this is sometimes called putting it ‘on retention’.
You’ll get a V778 certificate proving you still have the right to use the number.
Assign (‘put on’) a private number to a vehicle
If you have the right to a private number that isn’t currently being used, you can apply to assign it to a vehicle.
Transfer a number from one vehicle to another
To transfer a private number from one vehicle to another, you need to:
Take it off the vehicle you’re transferring it from.
Assign it to the vehicle you’re transferring it to.
You can also do this by post using form V317.