You need to fill in a P46 (Car) form if you provide any cars for private use by company directors or employees.

If you make any changes to the cars provided, you need to inform HMRC. For example:

you replace a company car - either tell HMRC straight away using PAYE Online or your payroll software, or report the change on your end-of-year forms

you stop providing a company car

you provide someone with an additional car, available for private use