AirHint found the following cheapest return flights from Denver (DEN) to London (LHR) in April 2026 (see full year).

Return flights

25 Apr - 30 Apr	Icelandair
02 Apr - 09 Apr	Icelandair
28 Apr - 06 May	Icelandair
30 Apr - 07 May	Icelandair
23 Apr - 30 Apr	Icelandair
15 Apr - 05 May	Air Canada
16 Apr - 19 Apr	Icelandair
01 Apr - 10 Apr	United
05 Apr - 16 Apr	United
14 Apr - 24 Apr	United
01 Apr - 14 Apr	United
08 Apr - 14 Apr	United
08 Apr - 06 May	United
15 Apr - 05 May	Lufthansa	direct
05 Apr - 12 Apr	United
26 Apr - 03 May	United
27 Apr - 04 May	Icelandair
24 Apr - 01 May	Icelandair
08 Apr - 06 May	Austrian Airlines	direct

Also check the deals for one-way flights from Denver to London in April.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

Book a cheap hotel in London

Cheap car rent in London

Cheapest return flights from Denver to London in April from 460€

Return flights