Heathrow to London Transfer?

a taxi will not be a 'bit more' It will be a LOT more.

take the tube. And maybe slightly less luggage. It's not a problem.

I'm leaning toward using a car service with greeter at terminal. I figure the 'help' with luggage at airport and hotel might be a plus. Of the three I mentioned (Exclusive Airports, simply Airports, and Just Airports) does anyone have recent experiences?
Re: The Picadilly line. I did some research and it looks like my flight will arrive at United Terminal 4. Would arriving at Terminal 4 make any difference regarding recommendations? How far is it from arrival gate to luggage pickup to Tube Station? BTW I appreciate the suggestion re Russell Station over Holburn for convenience. Thanks.

I thought that United fly into Terminal 1 but it doesn't make any difference. T4, T5 and T1/T3 each has its own underground station

The walk from the arrival gate to luggage pickup will vary depending on which gate you come into, but shouldn't be more than 10 minutes and the walk from there to the Tube station about the same (the walk to where the car would pick you up wouldn't be much quicker.

If you are planing on using the Tube during your stay then get an Oyster card at Heathrow Terminal 4 station - these will save you a LOT of money on your first and subsequent trips. Finally, in my experience, Londoners can on occasion be friendly and helpful and if so if you do struggle with cases then chances are someone will be right along to help.

"It will be a LOT more"
Not really, if taking what they paid for 2 transatlantic flights into account.
There are taxi firms online that'll do a 1 wayer from LHR to South Kensington for under £40. Only just over £20 more than 2 zone 6 cards. That's the option I'd choose as a retiree with 3 big bags anyway.

"Not really, if taking what they paid for 2 transatlantic flights into account" What a strange thing to say, of course it doesn't compare to the cost of flights, nor does it compare to the cost of a hotel in London or a slap-up meal in The Ivy, but in comparing the costs of travelling on the Tube with or without an Oyster card then it does save a lot.

As mentioned by others above, Russel Square Tube station on the Piccadilly Line is the most convenient, not South Kensington.

#2 and #14 You are comparing apples to oranges. With Oyster cards two singles from Heathrow to Russell Square are only £6 (£3 each) which is a lot less that £40 plus tip for a car service. The £17 (£8.50 each) that you quote is the Oyster card daily maximum charge for a full days travel on a Sunday, you do not get the car service for a full days travel for £40, so compare like to like.

After a red-eye from the East Coast (travelling eastwards is reddier-eyed than the return) and with 3 bags, I, as a fellow geriatric, have no hesitation in suggesting a taxi. Holborn to the BM aint that close carrying baggage.
The best suggestion is to try to get met by booking in advance, the sytem is minicab.

Why not phone up the hotel to see if they would organise a minicab at a fixed price. Most of these drivers are middle Eastern with just basic English, so it should be a quiet ride.

We have similar question. Travelling to Lisbon from USA with overnight layovers in London each way. Arriving LHR 9:30pm. 9/27 Depart for Lisbon @ 8:15pm 9/28.

Same on return flights - Leave Lisbon - arrive LHR 9PM, 10/5 depart for USA 5pm 10/6.

We would like to get some sightseeing in London but need to allow enough time back to airport using the tube.

Should we stay at airport hotel or can you suggest hotel in London - and how much lead time to get back to airport for international flights following day. Appreciate your advice.

I would say for both of those flights, stay in London. Allow 90 minutes on the tube to get back to the airport, plus your check-in time.

loads of hotels in London!