Taxi is the most comfortable way to travel from the airport to your destination. Taxis can be found at designated taxi stands outside the airports, just follow the 'TAXI' signs or ask the airport personnel. These taxis are colored in yellow and are almost always metered. However, not included in the metered charge are tunnel tolls which cost four dollars. Tipping the cab driver anywhere from 15% - 20% is customary.
A trip from JFK to Manhattan will cost a flat rate of $45 (plus tolls and tip). Keep in mind that from the airport it is customary for cab drivers to charge flat rates without turning on their meters. This, though, does not happen from Manhattan to the airport.
From LaGuardia to Manhattan, a flat rate anywhere from $17 to $27 is expected. This does not include tolls or tip.
From Newark to Manhattan, a flat rate ranging anywhere from $30 to $38 is expected.