As an example, I found this price on Delta departing New York JFK on Wednesday, September 25, returning from Madrid MAD on Wednesday, October 2.
Other dates are available on Delta for travel from late September through November. American also has this fare available on a few scattered spring travel dates in May. Travel to Europe Sundays through Wednesdays, and return from Europe Tuesdays through Fridays. A minimum stay of 7-nights is required.
This Basic Economy fare includes a carry-on bag plus one personal item. A checked bag costs $60 each way.
Seats will be assigned at random upon check-in for this price.
Delta's Main Cabin Economy fare is $427 roundtrip, which includes one free checked bag, advanced seat assignments, and allows ticket changes/upgrades for a fee.
See our fare details for booking info.
Need a room in Madrid? Here's what's available for the above dates on Hotelwatchdog.