On this page (4 sections)
The rule is a law, not a policy
Most airport guides describe smoking at JFK as a policy the airport has chosen. It is not. Terminal 4 publishes the position in its own rules and regulations, and the wording is worth reading exactly:
"Pursuant to New York City law, smoking cigarettes, including electronic cigarettes (e-cigarettes) indoors is illegal. Smoking is prohibited in Terminal 4 and aeronautical Operations Areas. Smoking is permitted only in designated areas immediately outside Terminal 4 (Arrival and Departure level). Smoking permitted 25 feet from building entrances only."
Three things follow from that. Indoor smoking is not a house rule that a sympathetic gate agent might overlook; it is against the law across the city, and the terminal is restating the law rather than setting one. Electronic cigarettes are in the same sentence, so vaping indoors is treated identically. And there is a distance rule attached to the outdoor areas, 25 feet from any building entrance, which is why the marked spots are set back from the doors rather than beside them.
Terminal 4 is the terminal that publishes this, but the law it cites is not terminal-specific, and no JFK terminal permits indoor smoking. There are no indoor smoking lounges at JFK, and an airline or credit card lounge is not a way around it either, because the indoor ban covers those rooms like any other. The lounges guide lists all 23 of them.
Where the designated areas actually are
Here is the honest answer, and it is the part every other page on this topic gets wrong by inventing precision it does not have.
Smoking areas are a mapped amenity, on the airport's services page, in the same list as ATMs, restrooms, water refill stations and charging points, each linked to a filtered view of the interactive map. So designated areas exist, and the map shows where they are on the day.
No list is published anywhere. No Port Authority page, and no individual terminal page, names a specific smoking-area location or gives a count. Guides that tell you there are six smoking areas at Terminals 4, 5 and 7, with positions, are working from aggregator sites rather than from the airport.
What you can rely on is the shape of it, from Terminal 4's rules: outside the building, on both the arrivals level and the departures level, at least 25 feet from an entrance. That is the pattern to look for at any terminal. Step out through the doors, look along the curb away from the entrance, and find the marked area or the ash receptacle. If you would rather know before you land, the airport map guide covers the interactive map and the filters that mark these.
One practical note about the curb itself. JFK's roadways are being re-cut constantly by the rebuild, and pickup and drop-off zones have moved more than once, so the spot you used last year may not be the spot today. The terminal overview tracks what has changed at each building.
The catch after security
This is the fact that decides whether the rest of the page matters to you. Every smoking area at JFK is outside the terminal building, which puts all of them on the public side of the checkpoint.
So there is no such thing as a cigarette between security and boarding. If you clear the checkpoint and then want to smoke, you have to leave the secure area, walk out to the curb, and be screened again on the way back in. At a busy terminal that is not a five-minute errand: the checkpoint line is the whole cost, and it can be long. Security waits run live on the security wait times guide, and they are worth a look before you decide.
The airport does have exactly one outdoor space past security, the Terminal 5 rooftop deck across from Gate 528, open 6:00 AM to 10:00 PM. It is not a designated smoking area, and the airport does not list it as one. Travelers who have been up there describe no-smoking signage at the entrance and on the terrace, and nothing official contradicts that, so do not go up there planning to smoke.
The practical consequence for a long international connection is worth stating plainly: plan your last cigarette before you go through security, not after. On a connection where you also change terminals, the airport requires re-screening anyway, so the outdoor stop can be built into that walk. On a same-terminal connection, going out and back in can cost you the gate.
Vaping, cannabis and what else counts
Vaping is smoking, for these purposes. Terminal 4's rule names electronic cigarettes explicitly and gives them no separate treatment, so a vape indoors carries the same status as a cigarette indoors, restrooms and gate areas included. Vaping outdoors goes in the designated areas with everything else.
Cannabis is legal for adults in New York State, and that does not make it fine here. The indoor smoking ban applies to it like anything else you would light, and the checkpoint is run by TSA, a federal agency that publishes its own position on cannabis. Check tsa.gov rather than assuming state law settles it, and do not plan on smoking it anywhere at the airport.
Lighters and matches. TSA's rules on what may go through a checkpoint change, and are TSA's to publish rather than the airport's, so check tsa.gov for the current position before you pack rather than trusting a guide page. That is genuinely the sort of rule that moves.
If you are at JFK for a long stretch and the smoking question is really a comfort question, two other pages cover the alternatives: the lounges guide for what a ticket or card opens, and the guide to sleeping at JFK for a long overnight, including the two places at the airport that rent a private room by the hour.