If a nanny drives as part of her (or his) job then they may use their own car or a car provided for them by their employer. Nowadays most nannies have their own cars but may not be happy to use them for work. If they are then there are several things to take into account:
Mileage – anyone using their car for work can be paid 45p/mile for the first 10,000 miles free of tax. If a nanny does over 10,000 miles this drops to 25p/mile. Miles done should be recorded (most people find a little notebook helpful) and submitted at regular intervals.
Insurance – nannies using their own car need to have business class insurance and the insurer needs to be aware what their job is.