For fall and winter travel, fly from nonstop from Newark to Madrid for $273 roundtrip on United.
Travel from September through March, excluding peak holiday travel in late December and early January. Travel to Europe Mondays through Wednesdays, and return from Europe Tuesdays through Fridays. A 7-night minimum stay is required and there is a maximum stay of 1-month to get this fare.
As an example, I found this price available departing Newark EWR on Tuesday, September 17, returning from Madrid MAD on Tuesday, September 24.
This Basic Economy fare includes a carry-on bag plus a small personal item. A checked bag costs $60 each way.
Seats will be assigned at random upon check-in for this price. You may pay a fee to choose a specific seat.
A Main Cabin Economy fare is $433 roundtrip, which includes one free checked bag, advanced seat assignments, and allows ticket changes/upgrades for a fee.
You can also save $30 by booking a $243 roundtrip Basic Economy ticket on certain third-party booking sites such as FareDepot. Booking via obscure third-party sites often means that there is no ability to change/cancel or there are higher than usual change fees. Since Basic Economy doesn't allow changes anyway, this may not be a big deal. Keep in mind that it may be difficult to cancel within 24 hours since you'll be dealing with a third-party that doesn't process refunds daily and it may not be possible to choose seats, even for a fee.
Related: How to Fly United Airlines
See our fare details for booking info.
This same fare can be found with more availability from New York (JFK) on American, Delta, and Iberia.
For more deals to Spain, check out all of our fares to Madrid (MAD), Barcelona (BCN), and Valencia (VLC).
Need a room in Madrid? Here's what's available for the mentioned dates on Hotelwatchdog.