how to take off sorn?

As soon as you buy the car you need to insure it and then pay the appropriate road tax.

Paying the tax automatically cancels the SORN (Statutory Off Road Notification). Note that you MUST get insurance for the car effective immediately, so get that sorted out BEFORE paying the road tax.

But expect two problems:-

1. You cannot legally test drive the car before purchase on public roads if a SORN applies to the vehicle.

2. You will be unable to buy road tax (Vehicle Excise Duty) if the car needs a current MOT but doesn’t have one. You will be able to insure it though and can legally drive it directly to the nearest available MOT station for a pre-booked appointment. But very few people take the risk of buying a car without an MOT and without a test-drive.

You'll have to contact DVLA and officially remove the SORN status from the registration.

you can buy a car that is sorn ..however to tax it you must have insurance ..and an mot ..then you can tax it and use on the road ....but only a fool would buy a sorn car ..how can you test it?

Yes, Yes and no.

You won't "tax it" You will pay the tax.

Grammar matters

When you buy the car and put everything in your name, there's no automatic anything. They don't care what the status was before you bought it, they want to know how it's being used now.

Here's how it works: I bought a used SUV from a mechanic. It was his mobile work truck, so it was registered, plated and insured as a commercial use vehicle. I bought it as a personal use daily commuter, so I registered, plated and insured it as a private passenger vehicle. Nobody assumed it would remain a commercial vehicle just because of the previous owner.