Denver International to London Heathrow
4658 miles great-circle distance, typically flown in 9h 46m with 4 airlines operating direct service from Denver International (DEN) to London Heathrow (LHR). Cheapest fares are usually in Jun (around $590 return), with peak prices in Jun (around $590). Departures on a Tuesday tend to undercut weekend prices on this corridor.
Flying from Denver International
Denver International sits 25 miles northeast of downtown Denver — a deliberately remote site that allows for six runways and almost unlimited expansion. The A Line commuter train runs every 15 minutes from the airport directly to Union Station downtown in 37 minutes for $10.50. United dominates the schedule with its largest non-Newark hub; Southwest and Frontier add heavy domestic capacity. Snow disruption is common between November and March, but the airport's ground-stop policy is faster than ORD's.
Arriving in London
London Heathrow is 24 km west of central London — the deepest transatlantic hub from anywhere on the US East Coast. The Elizabeth Line and Heathrow Express both reach Paddington (15 minutes Express, 30 minutes Elizabeth) for £25 and £13.30 respectively. US carriers (American, Delta, United, JetBlue) and BA dominate the corridor. Cheapest fares from US East Coast: late January and February; peak demand is June–August.
Who flies DEN to LHR?
| Airline | IATA | Flight time | Cabin |
| United Airlines | UA | 9h 46m | Economy |
| British Airways | BA | 9h 46m | Economy |
| Lufthansa | LH | 9h 46m | Economy |
| Icelandair | FI | 9h 46m | Economy |
4 carriers fly direct on this corridor. Frequencies vary by season — summer and winter holiday peaks see additional flights.
Best time to fly DEN→LHR
Synthesised from 12-month price aggregates. Cheapest months in green, peak in red.
Estimated baseline. Prices update on a 30-day cadence as Travelpayouts data refreshes. Cheapest day-of-week typically Tuesday.
Denver to London FAQs
Direct flights from Denver International (DEN) to London Heathrow (LHR) take approximately 9h 46m for the 4658-mile journey, plus 30–60 minutes of taxi, climb and descent. Total airport-to-airport time depends on cruise winds and air-traffic queueing on approach.
Jun is typically the cheapest month on this route, with one-way fares from $548. Jun is the peak — expect prices 2–3× higher. Book 4–8 weeks ahead for best fares; last-minute prices on this corridor rise sharply inside two weeks of departure.
4 carriers operate direct service from Denver International (DEN) to London Heathrow (LHR): United Airlines, British Airways, Lufthansa and Icelandair. Frequencies vary by season and carrier — United Airlines typically operates the highest weekly count on this corridor.
Electronic Travel Authorisation (ETA) required for US passport holders from 2025 — apply online, £10. Always check travel.state.gov for the latest entry requirements before booking.
London Heathrow (LHR) is the primary international airport for London. Allow 30–60 minutes for the ground transfer by train, express bus, taxi or rideshare depending on traffic and time of day. See the airport's official website for current train and shuttle timetables.