A Category S can be repaired following structural damage and you can use the vehicle again if it’s repaired to a roadworthy condition. If you want to keep a vehicle in category C, D, N or S, the insurance company will give you an insurance payout and sell the vehicle back to you. To keep a category C or S vehicle, you also need to send the complete logbook to your insurance company and apply for a free duplicate logbook using form V62. DVLA will record the vehicle’s category in the logbook.
Be aware that insurance can be harder to find for written-off cars and can be more expensive. Written-off cars are also worth less than their undamaged counterparts and can be hard to sell on. The car will have the 'Cat S' on its logbook as a permanent record.