A new car in Great Britain does not need an MOT until it is three years from first registration. After that the test is annual. The legal due date is printed on the MOT certificate, not guessed from the number plate.
You can take the test up to one month before the due date and keep the original expiry. Test later than that and you lose the leftover days. Driving without a valid MOT is an offence except when going to a pre-booked test.
What the calculator does not do
There is a free official MOT history service on GOV.UK. CarDiary does not look up your registration. Use the MOT due date calculator to plan from a registration date or last test, then save a reminder in the app next to VED and insurance.
Vans and taxis
Most cars, vans and motorcycles follow the 3-year then annual rule. Some public-service vehicles are tested more often. If the vehicle is used as a taxi, check the local licensing conditions rather than the private-car calendar.
