Cheapest return flights from St. Louis to Madrid in September from $564

AirHint found the following cheapest return flights from St. Louis (STL) to Madrid (MAD) in September 2025 (see full year).

Return flights

23 Sep - 07 Oct Air Canada
24 Sep - 01 Oct Iberia
30 Sep - 07 Oct Iberia
21 Sep - 28 Sep Iberia
09 Sep - 16 Sep United
02 Sep - 09 Sep Iberia
27 Sep - 04 Oct Iberia
15 Sep - 22 Sep United
18 Sep - 25 Sep Iberia
04 Sep - 11 Sep Air Canada
12 Sep - 19 Sep Iberia
06 Sep - 13 Sep United

Also check the deals for one-way flights from St. Louis to Madrid in September.

Skyscanner

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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