Heathrow to London Marriott County Hall & back?
 

Does anyone have a suggestion for the best way to get from Heathrow to the London Marriott County Hall & back? Any idea of cost for different options? Thank you!

Well - there isn't a "best" way for everyone. What time of day, how many of you, your budget, etc. Assuming that if you can afford the County Hall you are not on a really tight budget.

For more than 2 people a car service would be most convenient and cheaper than the train to Paddington and a taxi to the hotel.

The tube is the cheapest of course - but it is difficult (VERY crowded) in rush hour, takes a while and would a line change.

A car service is so easy that I sometimes use one even when traveling solo - relatively expensive but door to door service and no hauling luggage through train or tube stations.

There are various options:
Tube - Single journey (one way) would be about $8-ish per person and would take about 1hr or so.
Heathrow Express - Single journey is about $16 and then you can add on another $2 for the Tube connetion to Westminster. (NB I think you can get ar return - round trip - ticket on the Express for a pound or two more)
Taxi - $60 or thereabouts. Ouch!
Hire car - $40 (Ray Skinner's, Swiss Cottage Cars)
So, the Tube is the cheapest and not necessarily the slowest. I would take it. Pack light, use wheels, read a UK paper on the way into town and enjoy a new experience. After all, you can catch a cab anywhere!

We will have a lot of luggage; this is a 7-day vacation on our way to Australia for 3 weeks (our son's wedding), so we will be lugging a lot of stuff. Can someone explain the car service? Thank you!

Sorry, I forgot to say -- there are two of us.

A car service like Ray's is a good idea if you have a lot of luggage. He'll meet you as you exit Customs, holding up a sign with your name on. What a welcome sight after a long flight! He'll escort you and your stuff to the car and deliver you smoothly to your hotel door. See london-transfers.com

You might also want to search and review the posts about traveling light. I understand that weddings require special garments, but you might as well travel as light as you reasonably can. My family routinely does 3-week vacations wtih just carryons.

If you're only going to be in London for a short time, maybe you can pack a light bag for London and check the others at the airport.