It is posted online, if you are traveling at peak times you will need a reservation
it varies so call ahead
No reservations needed for just s passenger, but good idea for vehicles. Sometimes open slots do occur
It varies by the day so check the schedule on their web site https://www.longislandferry.com/Schedules/monthlySchedules.aspx I would recommend a reservation so you don't get disappointed if they are full when you arrive. Minimally check out how many spaces are left even if you don't reserve.
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