Although travelling in a taxi or minicab with young children has different regulations than when travelling in your own vehicle, it's still good for both passengers and drivers to keep up to scratch on car-seat and seatbelt laws. In most cases, children under 3 must always be in a child car seat, but the rules are different if: the child is in a taxi or minicab (private hire) the child is in a minibus, coach or van the child is on an unexpected journey, for example an emergency there’s no room for another car seat.
Taxis and minicabs (private hire vehicles) law:
If the driver doesn’t provide the correct child car seat, children can travel without one - but only if they travel on a rear seat:
-and wear an adult seat belt if they’re 3 or older. But a child under the age of 3 must not use an adult seatbelt.
General seatbelt use for adults is as follows:
You must wear a seat belt if one is fitted in the seat you’re using - there are only a few exceptions. You’re also only allowed 1 person in each seat fitted with a seat belt. You can be fined up to £500 if you don’t wear a seat belt when you’re supposed to. Children You must make sure that any children in the vehicle you’re driving are: in the correct car seat for their height or weight until they reach 135 centimetres tall or their 12th birthday, whichever is first wearing a seat belt if they’re 12 or 13 years old, or younger and over 135cm tall
You don’t need to wear a seat belt if you’re: -a driver who is reversing, or supervising a learner driver who is reversing -in a vehicle being used for police, fire and rescue services -a passenger in a trade vehicle and you’re investigating a fault -driving a goods vehicle on deliveries that is travelling no more than 50 metres between stops -a licensed taxi driver who is ‘plying for hire’ or carrying passengers
For the full interpretation of the law, you can visit Gov.co.uk