Can 2 adults and 4 small children travel around london in one taxi? all kids are out of car seats but under 10. also, can we taxi from heathrow in one cab or would we need 2?
You would do better to arrange a people carrier to meet you when you arrive. Then your whole family and luggage can travel together. Easy peasy.
Double check with them on the rules for children. It has gotten pretty strict here because it is based on the height/weight of the child. Older children use booster seats to help them fit adult seat belts better. I am not sure how this applies to taxis/minicabs though
As Jenufa says, book a car service for Heathrow to London. I haven't used them myself, but many people on the Fodor's board recommend Just Airports. There is a discount for paying cash. You'll need a MPV (minivan).
Just a quick translation to American English, a people carrier means minivan, describing the number of seats, rather than a type of company who move people. So a taxi or private car company would use a people carrier rather than a traditional black cab.
A taxi can be found at the taxi rank (like a line or queue for taxis) or booked ahead; a private car is a licensed book ahead only company without meters who take a journey for an agreed fee.
NEVER take a private car, minicab, etc, even if it appears to have official looking plates and stickers on it without pre-booking. If you do, its not insured!!
Never accept a ride in a car which has been touted around the airport. Its most likely not even licensed.
Normally there are 3 seats across the back and 2 facing pull down seats in a black cab. Everyone has to be in a seat, and all seatbelted.