JetBlue has round-trip flights from New York (JFK) to Grenada or Antigua (GND, ANU) for $269-$294, NONSTOP. Flights November to February. No Friday departures. Extended weekends available. No Thanksgiving dates.
JetBlue’s “Basic” fares allow for a carry-on bag and a small personal item (17 x 13 x 8 inches), like a Jansport SuperBreak backpack without a fee. You can avoid seat selection fees by accepting the randomly assigned seat at the gate.