How long is the flight from Denver to London?

Non-stop flights on DEN → LHR are typically around 9 hours. Connecting itineraries add 3–8 hours depending on the hub and layover.

Which airlines fly from Denver to London?

The main carriers on this route are British Airways, United. Codeshare and one-stop options add several more — the filter panel above shows every airline in the current fare set.

When is the cheapest time to fly from Denver to London?

Historically the lowest fares land in January, February, November. Summer (mid-June through mid-August) and the Christmas / New Year window are always peak. Mid-week departures (Tuesday–Thursday) typically beat weekend prices by 10–20%.

How far ahead should I book Denver to London?

Six to ten weeks ahead is the sweet spot for this route. Inside three weeks, fares tend to spike as airlines sell to last-minute business travellers. Award availability often opens 10–11 months out if you're booking on miles.

Can I book directly on destination.com?

The Book button on each fare opens the airline or OTA (Trip.com, Kiwi, Expedia, Booking, Priceline, etc.) that's actually selling that ticket. You complete payment there at the same price you saw here — we never add a markup.

DEN → LHR

Denver to London flights.

Live cached fares on Denver (DEN) → London (LHR), refreshed every 30 minutes. Non-stop and connecting itineraries side by side — compare airlines, times and stops, then book in one click.

Flying time
~9h non-stop
Airlines
British Airways, United
Cheapest months
January, February, November

Flex dates · cheapest nearby

Loading prices…

No cached fares for exactly 2026-06-08 → 2026-06-15. Showing recent fares on DEN → LHR — pick a different date in the calendar above or run a live search.

Denver → London · 4 fares

Cached from Travelpayouts · filter & sort below

Showing 4 of 4 results

Cheapest
Icelandair · FI 670
OutboundDEN → LHRMon, Jun 29 · 10:40 PM· 10h 35m· 1 stop
$619
one-way
Book →
Icelandair · FI 670
OutboundDEN → LHRTue, Nov 10 · 10:40 PM· 10h 35m· 1 stop
ReturnLHR ← DENWed, Nov 18 · 12:15 PM· 11h 25m· 1 stop
$749
total round-trip
Book →
Air Canada · AC 1074
OutboundDEN → LHRMon, Aug 17 · 5:25 PM· 10h 35m· 1 stop
ReturnLHR ← DENWed, Sep 2 · 5:00 AM· 14h 17m· 2 stops
$829
total round-trip
Book →
Air Canada · AC 3215
OutboundDEN → LHRTue, Oct 20 · 10:17 PM· 12h 11m· 1 stop
ReturnLHR ← DENWed, Oct 28 · 7:40 AM· 12h 35m· 1 stop
$843
total round-trip
Book →

Try a nearby airport

Thin routes often have more options from a neighbouring airport.

Denver (DEN) → London (LGW)

nearby destination

Denver (DEN) → London (STN)

nearby destination

About Denver → London

BA + UA daily non-stops. DEN's high altitude means ~9h eastbound but ~10h westbound. Seasonal demand spikes with ski-holiday UK traffic in Feb-Mar.

Typical non-stop flying time is around 9 hours. Major carriers on this route include British Airways, United. Fares are usually cheapest in January, February, November — book 6–10 weeks ahead and avoid school-holiday peaks (late June–August, Christmas–New Year) for the best pricing.

Month-by-month price guide: Denver to London

Live cheapest round-trip fare cached on DEN → LHR for each of the next 12 months. Tap any month and run a live search to confirm.

Apr
No data
May
No data
Jun
No data
Jul
No data
Aug
Peak
from $829
Sep
No data
Oct
Peak
from $843
Nov
Low
from $749
Dec
No data
Jan
No data
Feb
No data
Mar
No data

Cheapest next 12 months: November from $749 round-trip. Run a live search →

Booking window tip

Long-haul fares are most predictable when booked 10-16 weeks ahead. Inside six weeks expect sharp increases, especially in premium cabins. If you're paying with miles, search 330+ days ahead when award inventory first loads.

Questions, answered

How long is the flight from Denver to London?
Non-stop flights on DEN → LHR are typically around 9 hours. Connecting itineraries add 3–8 hours depending on the hub and layover.
Which airlines fly from Denver to London?
The main carriers on this route are British Airways, United. Codeshare and one-stop options add several more — the filter panel above shows every airline in the current fare set.
When is the cheapest time to fly from Denver to London?
Historically the lowest fares land in January, February, November. Summer (mid-June through mid-August) and the Christmas / New Year window are always peak. Mid-week departures (Tuesday–Thursday) typically beat weekend prices by 10–20%.
How far ahead should I book Denver to London?
Six to ten weeks ahead is the sweet spot for this route. Inside three weeks, fares tend to spike as airlines sell to last-minute business travellers. Award availability often opens 10–11 months out if you're booking on miles.
Can I book directly on destination.com?
The Book button on each fare opens the airline or OTA (Trip.com, Kiwi, Expedia, Booking, Priceline, etc.) that's actually selling that ticket. You complete payment there at the same price you saw here — we never add a markup.

Other ways to reach London

If your plans are flexible on the origin, these alternate departure airports also serve London on the routes we track.

Other popular routes

Keep planning

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