[08/01/2019 @ 6:17 PM CT] Price dropped to $480. Was $527.
American Airlines has round-trip flights from Houston (HOU/IAH) to Madrid (MAD) for $480-$542 with a connection. Flights October to March. 7-day minimum stay required.
Note: Carry-on bag is allowed for free on American Airlines. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.