JetBlue and United have round-trip flights from Newark/New York (EWR) to Sint Maarten (SXM) for $298-$308, NONSTOP. Flights May, June, August, September, October, December, January, February, and March. Very few weekends available. Origin/Destination reversible.
JetBlue’s and United’s “Basic” fares only allow a small personal item (17 x 13 x 8 inches), like a Jansport SuperBreak backpack without a fee. A regular sized carry-on bag will incur a bag fee.