If you have paid for a whole year's road tax up front, depending on how many months you have remaining it may be worth SORNing the vehicle if you are not using it for a whole month, as you will be refunded any unused complete months. You will need to re-tax the vehicle when you want to start using it again.

If you pay by monthly direct debit you will only save the payment while not using the vehicle, which would be around £45.