YES to going through immigration, collect your bags, and customs. You always have to do that at your first port of entry in the United States. NO to checking in again. You should be able to get your boarding passes for your JFK-MIA flight when you check in in UK. After you exit customs, there will be a counter where you drop off your bags for your final flight, assuming they are tagged all the way to MIA, which they should be.

Thanks Jeff, very helpful

Just look for the sign that says recheck or connecting flights.

Since this is an airline reschedule, you have some options. Where and when are you flying? If practical, I'd avoid JFK and seek to connect elsewhere. You can call Delta and they are usually accomodating in cases of rescheduled.

Connecting in Amsterdam or Detroit or even Atlanta would be preferable to JFK.

Agree with above, try to find a routing that avoids the need to connect ANYWHERE in the US just to put off the immigration procedures until you reach Miami - and leave the sexual assault by the Stassi - sorry TSA - until you leave the US.

Didn't see that you are flying to Miami. In that case, I would call Delta and try to switch to one of the following options, in order of preference:

If in business class:
1) Route through Atlanta
2) Route through Detroit
3) Route through JFK
4) Route through Paris
5) Route through Amsterdam

If in coach:
1) Route through Amsterdam
2) Route through Atlanta
3) Route through Paris
4) Route through Detroit
5) Route through JFK

This is utter nonsense.....connecting at JFK is no different than connecting at any other airport in the USA as far as immigration and customs are concrfned....in this case the passenger remains in the same terminasl....as soon as the passenger collects his or her baggage and goes through customs (generally just walk through and hand customs declaration to inspector), you check your bags right on the spot, go upstairs through security (even i you connect in Europe, security is extra tight perhaps unnecessarily so on US bound flights but that's another story) and go to the gate. No air train or walk or anything as you are on the same airline.

Sure a direct flight is better, I don't question that. But whether you connect in JFK, or ATlanta or wherever the procedures will be the same. Does it make sense to fly away from the USA from London to connect in AMS or CDG, both of which are very large airports?

Now if you told me you had to change carriers at JFK, I might agree there is a bit more of a hassle although the air train now functions quite well there, no different than the train tht connects terminals in Atlanta.

I don't know the time between flights and all that and maybe there are better connectons but there really is no great hassle in this particular case at JFK. As always, it will depend on weather and the number of flights arriving at the same time just the same as in Atlanta

JMHO but I go through JFK all the time and they are no worse than any other airport for the most part especially if the connecton is on the same airline.

This is utter nonsense.....connecting at JFK is no different than connecting at any other airport in the USA as far as immigration and customs are concrfned....

Except the lines are longer at JFK. And the customs area for T3 is incredibly unpleasant. Is connecting there the end of the world? Of course not, but I would choose the other options over JFK.

in this case the passenger remains in the same terminasl....

It depends upon whether he lands in T2/3 or T4. Landing at T4 will require switching terminals. Also, one should bear in mind that T2 and T3 are pretty dumpy, if functional.

I have come into JFK on international flights from LHR and didn't notice anything all that bad....also I don't know the opening date but Delta is abandoning T3 (which is the old Pan American terminal) and moving into brand new quarters in the snear future I believe.

My only point and I will stick to it is that connecting at JFK (and the lines are not always all that long, especially for US citizens) is really no different than anywhere else.

Of them all, probably the worst might be CDG.

Delta is not leaving T3 for at least another year or two.

As for CDG... It is not the best, but it is far better than the reputation. Walks are long, but lines are well-managed and rarely a problem.

Does it make sense to fly away from the USA from London to connect in AMS or CDG, both of which are very large airports?

Looking at Kayak one stop routings run between 12 & 13 hours whether you fly via JFK, Detroit, Tampa, Orlando, Washington DC, Frankfurt, Paris or Madrid. Even going via Zurich only makes total travel time less than 14 hours.

By going through a European hub you don't go through any immigration checks until Miami so no worries about standing in a queue waiting to be processed when the clock is ticking away. You avoid having to collect your baggage at the connecting airport and you don't have to go through forcible sexual assault. (Well you do but it only happens when you head home and if you do the same route home it only happens once instead of three times).

Note I'd also recommend doing similar for flights to the UK if your final destination isn't London and can't find suitable direct flights.

You avoid having to collect your baggage at the connecting airport and you don't have to go through forcible sexual assault. (Well you do but it only happens when you head home and if you do the same route home it only happens once instead of three times).

This makes no sense. Care to explain your math?

I agree with Alan. It is better to not go through a connection in the US in this case, but I also think JFK shouldn't be worse than other US entry points, at least for US citizens. If one is really about lines, and travel out of the country more than a few timew a year, go get Global Entry.

This makes no sense. Care to explain your math?/i>

If you fly via a US airport you get groped in both directions at the connecting airport plus when you leave for home you get groped (in this case) at Miami - so once going to the US, twice on the way home. If you fly into & out of Miami you only get groped the once - when you leave for home.

If you fly via a US airport you get groped in both directions at the connecting airport plus when you leave for home you get groped (in this case) at Miami - so once going to the US, twice on the way home. If you fly into & out of Miami you only get groped the once - when you leave for home.

But you'll get groped at AMS or CDG, too...

The only thing that really changes is whether you get groped by a Dutchman, a Frenchman, or an American. That and whether you have to remove your shoes or remove your belt. Other than that, the security is pretty much the same on both sides of the pond.

The fact is, at the insistance of the US government whether rightly or wrongly, all major airports have put in stricter security for flights to the United States. I remember one time when I didn't book the airline, a tour company did, that I was routed to JFK from LHR via Frankfurt. What a messy experience and the planes were on time. All US departures were in a very out of the way location at Frankfurt and even after going through the standard security for a connecting flight I was wanded again and my carry ons gone through. Connecting through a US airport you will get the standard US security check at the connecting point bt none of this at the gate business.

Again, nobody is going to try to tell you a connecting flight is better than a non stop diret. That would be an absurd statement, once is enough. But once you do have to connect, then connecting at JFK, at least from my experience, is no better or worse than connecting in other places although I will accept that Alan is sort of correct namely you don't have to carry your baggage when connecting in Europe but Alan the carying of baggage at JFK in this situation consists of going from the carousel to the custms inspector and a few more feet to drop it off, already tagged, back to the airline. It really is no big deal (and in a sort of way better as the passenger knows his or her baggage is on this side of the pond....on the connecting flight I described above upon arrival at JFL from Frankfurt I waited and waited till all the baggage came down and when it didn't and went to the airline discovered my bag had not made the connection. That happens but why did I have to wait an hour to find out?