Customs at LHR

It depends on whether you have checked baggage or not, and which terminal you come into and depart from. The main concern is immigration, not customs, but if you do it right you stay "airside" and can transfer between terminals without going through passport control. If you have to reclaim an dre-check baggage, however, you will have to go throug himmigration and likely will not make that short of a connections.

If you have checked luggage, then you will have to go through immigration and customs. If that is the case, I would not book a plane with only 2 hours. It can take up to an hour to get through immigration. Then you would have to possibly switch terminals and come back through security (could be quick, could be another hour). If you have carry-on only and check-in online for the second flight before you depart the U.S., you should be able to stay airside without going through immigration. You will still go though a security check airside and you may need to transfer terminals. Personally, I never book a separate ticket from LHR on the same day as my transatlantic flight. I've been delayed multiple times coming into LHR. Two years ago, my flight from DC was 2.5 hours late. Twice, my flight from the U.S. into LHR has been delayed and I've missed my connecting flight; however, since I was on one ticket, I was put on next flight.

If you have carry-on bags only, you skip immigration and customs and stay "airside" even if you change terminals. If you're checking luggage it depends on the airlines you're flying and whether or not they interline bags. If they do, you check your bag at SFO all the way through to Paris and you stay airside at LHR. If they don't, and Virgin Atlantic and British Airways don't, you get to go through passport control, customs and change terminals. If this is the case, you won't make it in two hours. Check out the website below and take heed of minimum connection times: http://www.heathrowairport.com/heathrow-airport-guide/flight-connections

A lot will also depend on hat other planes land when you do. But, unless your baggage is checked through to your final destination, this does sound extremely tight

No is the simple answer. Heathrow is large, flights are late, immigration can take forever. Why stress? Either stay overnight, Yodel at the airport is practical, or take a later connection.

Would anyone recommend the train from LHR to Paris?

The London-Paris train is great. It doesn't leave from Heathrow, however; you have to go into London and catch it at St. Pancras station.

Arin, If you have already bought your ticket to LHR and you want to continue on to Paris on the same day, you might as well fly since you will be at the airport. The same issues will apply with the train. In order to get reasonably priced airline or train tickets, they are normally non-refundable. The main thing is that you need to choose your flight to Paris based on how much risk you are willing to accept. If you had booked a flight to Paris with a connection in London on one ticket, then the airline would be responsible for getting you to your final destination even if the first flight were delayed. When you book separate tickets, if you miss the second flight then you are responsible. You can mitigate some of this risk by allowing more time between flights or carrying on your luggage or choosing a flight that departs from the same terminal.

NO! You might get lucky and make the flight, but... I did this exact same thing this year and it would have been very tight with that "connection" and you aren't allowing ANYTHING for a late arrival. (Which happens a lot) I would allow a minimum of 4 hours. There's a "time cost" to the "financial savings" you get via this method. Realize that if you miss the LHR to Paris flight you get to buy a walk up ticket. I was prepared to buy a walk up chunnel ticket for example.

(By the way, my assumption is the "hopper" flight is not connected to your original flight which is how it sounds here. If it's a through ticket with just a layover in LHR then you have more protection. If the LHR arrival is late the airline will help you if they booked you alll the way through!)