Direct vs Connecting? / Enough Time?

It doesn't depend on the Airline. But it strongly depends where you are booking with:
If you book via a 3.party-provider, you almost always get cheap flights with "self connection". This means, you get 2 different flights, and if the first flight is late, times changed or even cancelled, and you miss your second flight, you would be on your own, have to pay annother flight just out of your pocket.
If you book with the airline directly, booking a "through" flight with one ticketnummer, the airline is responsible. If your first flight is late then the airline have to book you on the next available flight for free.
Nevertheless, I always would book a bit longer time for any stopover, just to avoid any stress. One hour would be much too short for me, because it could take up to half an hour before you even can leave the airplane (depending where your seats are).

TY REI: I usually look at Google Flights and book that way, sometime go direct to the airline. TY for reinforcing going direct if possible. And yes, 1 hour would be quite stressful, all the stars would have to line up for it to work. Too risky. TY

Maybe take a look at JFK-LHR (which has some of the lowest transatlantic fares) and then Eurostar. There is a similar risk that if your flight is delayed, you miss the train.

TY G3. Hadn't even considered that means but will take a look. I've heard horror stories about LHR but maybe they are undeserved. TY

G3: Checked the flights and they are quite reasonable for direct in/out of Newark. no need to go to JFK. Eurostar would be approx. 4 hours @ $85. Got me thinking..TY

I've discovered that travel isn't always about sticker price, but the value associated with each cost. If a direct flight is going to reduce the opportunity for missed connections or stress, is it enough of a value to justify the increase in expense? Only you can decide for yourself how you feel about this. Any connection increases risk.

One thing to consider: A connecting flight through LHR (one ticket) will not involve going through passport control. A connecting flight through other airports may involve this. You will go through security again at LHR, but it is usually fairly efficient.

If you choose the LHR then Eurostar route, be sure you have an ETA for the UK. If you enter the UK you are required to have one. Simply transiting airside at LHR does not require one.

If I have a shorter connection on the way home, it worries me less than a shorter connection on the way to my destination. I don't mind coming home a day later if I miss a flight (the beauty of being retired), but I hate to miss a day of my trip on the way there.

It is immigration (people), not customs (stuff), that should be your concern.

A comfortable connection depends on the airline and the airport. For example, connecting through Oslo or Copenhagen with SAS is very efficient. I wouldn't worry. Worst case scenario is they put you on a later flight at their expense.

Unless you're saving hundreds of $$$, don't fly into London and then take the Eurostar. You will have the expense of getting to St Pancras, you need to arrive at St Pancras 75-90 minutes before departure for check-in and passport control AND you're doing all this with a foggy brain after your overnight flight. And don't forget to include the cost of the ETA for the UK.

I would want more than an hour. Transiting through a Schengen country airport means having to go through immigration.

Not sure when your flight will take place but if you haven't registered for the new EES system, immigration might take longer than usual.

Have you looked at Icelandair and connecting through Reykjavik? They are pros at connections.

If you are able to navigate a large multi terminal airport like Newark or JFK there’s no reason to fear Heathrow. Heathrow as a nice connecting flights tool that outlines what to expect. If you find flights you are considering then pop them into the tool to see what to generally expect.

Have a great trip!

https://www.heathrow.com/connecting-flights

TY Carol, Jean, Fran k, and Rocket. Sorry for the delay here. I appreciate the suggestions and comments. I love getting the best info on the RS Forum. You guys are the best. TY again.

I would not take the Eurostar unless it saves you a lot of money.

If you would list the connecting airports and the amount of time allowed for transit, people might be able to make suggestions as to what would be the better choice.

I often take flights with short connections because I hate waiting in airports. When I do that, I consider how easy the airport is for connections, whether there are multiple flights a day to my destination, and would I be ok if I got stuck overnight in that city. Of the airports you mentioned above, Copenhagen would likely be my choice for connecting.