Will I Be Jetlagged?

Should you sleep on a flight from London to Las Vegas?

London to Las Vegas crosses 8 time zones westbound. Westbound routes are often easier because your body clock can delay.

Local time in LHR

Auto-calculated in LAS

LHR
London Heathrow Airport
LAS
Harry Reid International Airport
14:00 - 16:3710h 38m flight-8 hours

Sleep, but keep it controlled

Reduce sleep debt without sabotaging your first local night.

Sleep window: 5 hours 40 minutes - 9 hours 50 minutes after departure (max 4 hours 20 minutes)

First day plan: Stay active after landing. Use caffeine in the early part of the day only. If needed, cap naps to 90 minutes.

Why this recommendation?

  • This is a long-haul flight (10h 38m), so unmanaged sleep debt is a major factor.
  • Large shift (8h): full adaptation often takes around 6-8 days.

Tips for your flight

  • Hydrate consistently during and after the flight.
  • Use caffeine early only; avoid it later in the destination day.
  • Sleep in a bounded window, then wake and transition to destination timing.
  • Get bright light exposure after landing to reinforce destination daytime.
  • If possible, shift your sleep by 1-2 hours/day before departure.
  • Optional: melatonin 0.5-3mg at destination bedtime may help adjustment.

Route intelligence

Time difference: -8 hours. Direction: westbound.

Typical nonstop duration is around 10h 38m for this route distance.

Typical advice for this route: protect your first local night while managing fatigue. The best strategy depends mostly on departure/arrival timing, not just the route itself.

Understanding Your Flight

Time Zone Change

LHR12pm3pm6pm9pm12am3amLHRlocal timedeparting 2pm−8h weststretches by 8hLASlocal timearriving 4:37pmLAS4am7am10am1pm4pm7pm

Flying west stretches your perceived day - clocks at LAS are 8 hours behind, so your day feels longer than 24 hours. Your body will want to sleep and wake earlier than locals in LAS. The daylight window is 0.5h shorter at LAS, affecting how quickly light exposure can reset your clock.

Prefer the stretching vs squishing framing? Why this route stretches your day

Body Clock vs Local Time at Arrival

Your body clock

Based on LHR time on arrival

Local arrival time

Harry Reid International Airport

FAQ

Should I sleep on a London to Las Vegas flight? Usually yes for long-haul flights, but timing matters. Use the departure time input to get route-specific sleep windows.

Is jet lag worse flying there or back? Eastbound is usually harder than westbound for circadian adjustment, especially across large shifts.

How long does recovery usually take? For a 8-hour shift, many travellers need multiple days to fully adjust.

What should I do after landing? Follow the first-day plan in your recommendation card and use local light timing to reinforce the destination schedule.

8,395
kilometers
No
red-eye flight
No
crosses day/night

These recommendations are educational, circadian-informed guidance and not medical advice. If you have a sleep disorder, are pregnant, take sleep-related medication, or have ongoing fatigue concerns, consult a clinician.

Read more: run your flight timing · jet lag guides · evidence and methodology