Norse Atlantic Airways has round-trip flights from New York (JFK) to Berlin (BER) for $334-$373, NONSTOP. Flights in May, October, and November. Departures on Monday, Tuesday, Thursday, and Sunday. Very few extended weekends available. Origin/Destination reversible. No Thanksgiving dates.
Some small OTAs on Skyscanner and Google have this for as low as $328; which is cheaper than the airline. If you plan on booking there, beware of any site that charges a fee to cancel a ticket within the 24-hour “free” period. Use unknown booking sites at your own risk.
Norse Atlantic is a budget carrier. Fares do not allow for a free carry-on bag. Only a small personal item (17 x 14 x 8in) like a Jansport SuperBreak backpack is allowed without additional fee. You can avoid paying for seat selection if you accept the randomly assigned seat prior to boarding. Checked and carry-on bags cost between $45 and $70 each-way, depending on weight and size.
Click for more details and booking links Nonstop Flights: New York to/from Berlin $328-$373 r/t [May, Oct-Nov] (No Thanksgiving) (Budget carrier) – Norse Atlantic Airways