New York is typically 7 hours behind Helsinki. When it's 5:00 PM in Helsinki, it's 10:00 AM in New York. Both cities observe DST but on different schedules.
During the brief DST transition weeks (2-3 weeks in March and November), the difference can be 6 or 8 hours. Finland uses EET/EEST, New York uses EST/EDT.
Optimal window: 8:00 AM - 10:00 AM New York time (3:00 PM - 5:00 PM Helsinki). Morning New York catches afternoon Helsinki.
Finnair promotes Helsinki as a gateway between North America and Asia with its "Via Helsinki" routing. The Arctic route makes Helsinki one of the fastest connections to Asian cities.