Read both clocks before planning sleep.
| LHR clock | JFK clock | Destination date |
|---|---|---|
| 07:00 | 03:00 | Oct 26 |
| 12:00 | 08:00 | Oct 26 |
| 18:00 | 14:00 | Oct 26 |
| 22:00 | 18:00 | Oct 26 |
January 15, 2027: -5 hours; July 15, 2027: -5 hours (destination minus origin). These two seasonal examples have the same difference; always check your own travel date.
Westward travel often asks for a later body-clock schedule. Holding out for an appropriate local bedtime can be difficult when the departure clock already feels late.
An example shape for this trip.
An educational example, not a personal schedule. Precise light timing depends on your internal clock as well as the itinerary.
Two or three days before departure
Look at the LHR evening row above beside the JFK clock. If feasible, make a modest sleep-schedule shift toward your destination without cutting your sleep short.
Flight day
Keep the ticket’s LHR departure date and JFK arrival date visible. Plan a realistic opportunity to rest; avoid relying on alcohol for sleep. Caffeine close to intended sleep can make rest harder.
First local day
Use New York local time for meals, activities and the coming bedtime. This smaller long-haul clock difference can still disturb sleep. Anchor your first local evening to the destination date rather than treating tiredness as a cue to take a long late nap.
Following days
Recheck how rested you feel before adding demanding activities. General advice is not a promise of a fixed adjustment time; use your personalized schedule and clinical guidance when appropriate.
Sources · CDC jet lag guidance · Airline route/network reference · checked 2026-10-26
Airline service and dates can change. This is a travel-planning guide, not a timetable or a claim that a nonstop flight operates on your date. Flight-duration estimates are omitted.
A few useful answers.
What is the LHR to JFK time difference?
On 2026-10-26, New York is 4 hours behind London. Seasonal offset examples: January 15, 2027: -5 hours; July 15, 2027: -5 hours (destination minus origin). These two seasonal examples have the same difference; always check your own travel date.
Is this an westward trip?
The shorter geographic direction from LHR to JFK is westward. Direction and civil-clock offset are different concepts, especially around the date line. Neither alone determines your personal light schedule.
Is the sample a personal plan?
No. It is an educational outline, not advice for your sleep schedule or health. The app uses your itinerary and usual sleep to create a plan; your first complete itinerary is free.