Meeting up with friend at Heathrow ....

You didn’t say where you were going from Heathrow but, in my opinion, 2 1/2 hours is long time to wait in the airport after an international flight.

I would suggest you head to the hotel as that will be a more comfortable place to wait. If you are staying in London, a taxi will be the most expensive way to travel. There are many less expensive options. Where are you staying?

Are you counting the time it will take for you to get through passport control (immigration) and customs? Sometimes it can take 20-30 minutes just to disembark the plane (not a Heathrow specific comment). And of course depending on if your plane is on time and goes with directly to the gate. Waiting for a checked bag too. If not accounting for these things, they may eat up much of your wait time.

And of course, your friend's flight might also be delayed, or early. So best figure it out when the time comes.

Have your friend down load WhatsApp on their phone. You do the same. Use it to communicate.

Depending that your flight and hers arrive at scheduled times it’s best for you realize Immigration can be lengthy. A variety of factors such as how many staff are on duty or how many flights deplaned at the same time will affect immigration.

Is this your first time at Heathrow?
Why the cab?

Why not the Elizabeth Line to Paddington?

OR

There are shops and cafes and many seats where you could wait. Not going to be as long as you think

Thanks for the replies. I didn't feel up to wrangling my luggage on the tube, so I took a cab. As it turned out, my friend didn't get to the flat for a few hours, so I am very glad I didn't wait at the airport. I've been to London before and when I traveled with my husband we often took the Heathrow express into Paddington and then the tube or a cab.

For future reference there is also the Elizabeth line. Gets you to Paddington or many other areas of London. Not quite as nice as the express as there do not seem to be dedicated luggage racks. But for me it’s much nicer than the tube.

Thank you, Rocket. I'll keep this in mind for future visits.

If you prefer the car option, prebooking a car service will usually be cheaper than a taxi. You know the price when you book the reservation. They meet you as you exit customs and drop you in front of your accomodations.