Is it illegal to drive without a spare tyre?

Spare tyre requirements

There is no UK law that states you must have a spare tyre in your car. As a result, many new cars do not include spare tyres, instead using run flat tyres or a tyre repair kit.

That said, it is a good idea to have some form of puncture solution available, whether an actual spare wheel, a tyre repair kit, or run flat tyres.