Delta Airlines and code sharing SkyTeam members KLM and Air France have round trip airfares travelling from Phoenix (PHX) to Madrid Spain (MAD) for $444, making one stop. Most flights are operated by Delta Airlines.
Departs PHX: April 5-6, 8-20, 22-27, 29-30; May 1-4, 6-10, 13, 15-17, 20-23, 29, 31; June 2-6
Returns: good availability thru June 21, limited Saturdays.
Use dates and book it on Priceline [priceline.com]
or Expedia [expedia.com]
. Bundling hotel with airfare will save money.