Yes, but if the car is unroadworthy you can still be prosecuted if stopped and inspected, as you can be if it's unroadworthy and you are on your way to MOT.


from, http://www.direct.gov.uk/en/Motoring...icle/DG_069671

Driving an untaxed vehicle to an MOT test

You can drive your vehicle to and from a pre-arranged test at an MOT test station as long as you have adequate insurance cover.
This also applies to vehicles being driven to and from a pre-arranged test at:

• a Vehicle Inspection Check (VIC) test station
• an approved weight testing station and reduced pollution test station