Mykonos Island National Airport (JMK) sits about 4 km from town. As airport transfers go this is a short one, and a taxi or a pre-booked car solves it.
The two arrivals, which are not the same
By air: JMK, about 4 km out, and a short run in.
By sea: ferries dock at the New Port at Tourlos, about 2 km north of Chora, where buses and transfers meet the boats. If someone has told you the port is in town, they are describing the old harbour, not where your ferry arrives.
Worth knowing in advance if you are arriving on one and leaving on the other, which on Mykonos is common - many people fly in and ferry out to Santorini or Paros.
Chora is pedestrian-only, and that is the real catch
Chora is pedestrian-only and deliberately maze-like - the lanes were laid out centuries ago to confuse raiding pirates, and they still work. Vehicle access to much of the centre is restricted, so “in town” often means a walk from wherever a car can stop.
The consequence for this journey is simple and it catches people every season: arriving with luggage is a genuine exercise. Your driver cannot take you to the door of most places in Chora, and the last part is on foot through lanes designed to disorient you.
Plan for it rather than discovering it at midnight. If you have heavy bags, it is the strongest argument there is for booking somewhere that can tell you exactly where a car can stop.
Whether you need a car at all
For a Chora-and-beaches trip, mostly not. Parking anywhere near Chora is a genuine headache, so for most trips the buses beat a rental. KTEL Mykonos runs from two stations in town, Fabrika and the Old Port, out to the south-coast beaches.
Rent one if your trip is about reaching the quieter corners on your own schedule rather than the famous beaches. Where to stay in Mykonos covers how the areas map onto that.
The leg before this one
If you are connecting off a flight into Athens, the ferry from Rafina is usually the better boat - it is closer to Athens airport, so it wins for airport connections rather than city stays. Athens to Mykonos is the page for that decision, and it matters more than this one does: the route where the port you choose matters more than the boat.
Our Mykonos guide has the practicalities, and things to do in Mykonos covers the town and Delos offshore.