Avg fare for taxi ride from LaGuardia Airport to West 45 street in NY, NY Times Square at 11:30 am
No more than $50.
It should be about $45 depending on traffic (with all the airport construction, this could be an issue at any hour), but I recommend the NYC Airporter Shuttle if you aren't in a huge hurry. Might take up to an hour for your trip, but they run every 30 minutes, pick up outside every terminal of LaGuardia Airport, drop off at W. 42nd/Port Authority Bus Terminal, and its a flat rate of $28.
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Buy a pass at the airport good for subway and buses in the city. We took a bus from LaGuardia Airport to the northern end of Manhattan (It's been too many years), walked a couple of blocks to the subway and took it to our hostel. Best value for the week.
Apologies to Amy L., but I advise against the Airporter. It used to be a very reliable service and a good value, but the last time I tried to use it, it was in a state of complete chaos. It took over two hours to make a trip that should have been 20 minutes, maximum. I thought it might have been a random occurrence, but online reviews suggest the service is frequently slow and haphazard. It is cheaper than a cab, but probably not worth the headache.
Its a flat rate from any NYC airport including LaGuardia - approx $50 to anywhere in Manhattan
It's approximately $35-40 taxi fare depending on traffic
There is a set far to and from the airport. It includes bridge tolls and I believe it is $54, the last time I took a cab; there may have been an increase.
Trips from the airport to city are priced fixed in yellow cabs
I believe it is $35-40