AirHint found the following cheapest return flights from Houston (IAH) to London (LHR) in September 2025 (see full year).

Return flights

30 Sep - 07 Oct	Air Canada
24 Sep - 30 Sep	Air Canada
30 Sep - 09 Oct	Air France
28 Sep - 14 Oct	Virgin Atlantic
24 Sep - 01 Oct	Delta
23 Sep - 29 Sep	Virgin Atlantic
29 Sep - 13 Oct	Virgin Atlantic
23 Sep - 14 Oct	Air Canada
24 Sep - 30 Sep	United	direct
30 Sep - 21 Oct	Air Canada
24 Sep - 01 Oct	United	direct
30 Sep - 09 Oct	United	direct
30 Sep - 07 Oct	British Airways	direct
25 Sep - 28 Sep	KLM
24 Sep - 28 Sep	United	direct
25 Sep - 28 Sep	United	direct
21 Sep - 30 Sep	Spirit Airlines
22 Sep - 29 Sep	Spirit Airlines
23 Sep - 29 Sep	Lufthansa	direct
18 Sep - 22 Sep	Spirit Airlines

Also check the deals for one-way flights from Houston to London in September.

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.

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Cheapest return flights from Houston to London in September from $492

Return flights