You can find these deals stacked up over at Google Flights. From JFK you can get to Barcelona for $377, Madrid for $381, Mallorca for $391, Tenerife and Minorca for $393, Alicante and Ibiza for $395, Porto and Valencia for $398, and Malaga for $399.
Flying out of Boston you can head to Barcelona for $387, Madrid for $381, Tenerife for $393, Mallorca for $394, Ibiza for $395, Minorca for $397, Porto and Bilbao for $398, and Alicante for $399. All of those prices are all-in round-trip, making them a damn good deal even if it's a bit more than you'll find by giving your couch a shakedown for change.
The date ranges available vary, spanning February through May, with many of the good deals looking like they pop up in late February. But the tickets will no doubt go quickly, as good prices on a European vacation always do.
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