We will be flying from SFO to Copenhagen and have a 3 hour layover in Heathrow. We are fying United on the Atlantic leg and SAS (booked through United) from Heathrow to Copenhagen. If I read everything correctly, it appears that we will stay in terminal 2 for our layover. We will be coming back to London for 4 days after Denmark and Paris. I have one Oyster card but will need 3 more. Does anyone know if there is there anywhere inside security to buy an Oyster card? It's not mandatory that we get them then, but it would be something to do while we are killing time and it would then be done when we arrive in London from Paris.
I'm afraid it looks like you have to wait until you get to the Tube office.
If you do not have a Visitor Oyster Card, but still plan to travel
around London for more than a day, you can buy an Oyster card at the
airport Tube station. Exit the airport and follow the signs for the
Underground. You can purchase an Oyster card at the cashier window.
I've seen many Oyster card machines throughout Heathrow, but I don't think I've been in Terminal 2 specifically, and their web site doesn't seem to be showing details of locations of vending machines. It could be possible that you'll find an Oyster card vending machine during your layover, but it could be good to wait until your return anyway, it's super quick to get them from machines, and that way you would not run the risk of misplacing them in your other travels.