| Cheap Flights: San Antonio to Madrid $513-$538 r/t â Delta Delta has round-trip flights from San Antonio (SAT) to Madrid (MAD) for $513-$538 with a connection. Flights in April, August, September, and October. No Fridays or Saturdays. Very few extended weekends available. Note: Previous deals were about -$50 cheaper than this. We think there is a good chance that the price will drop below what it is right now. Note: Carry-on bag is allowed for free on Delta. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate. We donât charge a subscription fee. All of our deal notifications are available for FREE via Instagram, Facebook, Twitter, our Webpage, and our E-mail list. If you are paying someone a subscription fee for our content, you are being ripped off. Read More Cheap Flights: San Antonio to Madrid $513-$538 r/t â Delta . | 