You can do your MOT test up to one month minus one day (29 days) before your current MOT certificate expires without changing the renewal date for the next MOT. For example, if your MOT is due to expire on June 12th, you can have the MOT test done as early as May 13th and still keep the same expiry date the following year. If you do the MOT test earlier than this, the new expiry date will be based on the date of the early MOT, not the original expiry date. This allows you to book conveniently without losing any validity time on your MOT certificate.