Entwood is 100% correct, Trade Plates remove the need for the vehicles to have its own tax. They are effectively portable tax discs for my use or anyone I employ. T Plates do not exempt from MOT. Strangely 90% of the police officers I speak to think they also count for MOT aswell.
I didn't know that. I test drove my daughter's car on the trader's Trade Plates, and the car was out of MOT

Most people don't know tbh Andy. I know I can get away with no MOT driving with T plates. But there's always that part of me that know's it's not actually legal, and as clearly I need my driving licence and I am now officially to become a magistrate, I must ensure everything is always done properly.
Does anyone remember PC Angus Nearn (incorrect spelling of last name I think) who was on Traffic Cops?
He was the one who knew all about HGV driving, trailers etc, the need to have tacho if towing for a business etc?
It just takes a police officer who is very good at his job, and there you are - caught!