Cozumel international airport (Airport Code: CZM) receives direct flights from Atlanta, Charlotte, Chicago, Dallas, Denver, Detroit, Halifax, Houston, Miami, Minneapolis, Montreal, and Toronto as well regional flights from Mexico City.
However, most of the travelers fly into Cancun (Airport Code: CUN) which generally has more flights, then take a bus or van south to Playa del Carmen and take the ferry across to Cozumel. A shared van from Cancun airport to Playa Del Carmen will cost around 300 pesos per person one-way, where a bus will be around 130 pesos (or $12 USD if you do not have pesos handy) per person one-way.
Also you can take a small plane to Cozumel from Cancun airport’s domestic terminal. It takes just 15 minutes and the trip is an amazing experience for about $75 USD per person one way.
There are hourly rides to and from Playa del Carmen, costing about 156 pesos ($13.50 USD) per adult each way. There are two companies, Ultramar and MexicoWaterJets so buy a single ticket because you may need to use the other ferry company coming back and the tickets aren’t transferable (two one-way tickets cost the same as a return ).
A car ferry leaves from Calica, a few kilometers south of Playa del Carmen (pass Xcaret). The car ferry from Puerto Morelos no longer exists! There are 4 ferries each day, but the first at 04:00 AM and the second at 08:00 AM are specially for supply and logistics of the locals and islander. So take the ferry at 12:15 PM and 06:00 PM. From Cozumel back to the mainland you can take all ferries: 06:00 AM, 10:00 AM, 04:00 PM and 08:00 PM. As of October 31 2015, rental cars are allowed and cost 400 pesos for the car and driver. You purchase your tickets in the wait line at the dock. Recommend you get in line at least one hours before the scheduled departure time. But parking in Cozumel city is a nightmare and you will be ticketed and they will remove your rear license plate that can only be retrieved at the policia station on Quintana Roo Ave about 300 feet beyond the intersection with Ave Rafael E melgar (the main road that runs along the waterfront) at a cost of 300 pesos if you pay within 24 hours,600 pesos after 24 hours.
Cruise ships often visit the island. A few can dock virtually downtown. A larger pair of piers lies about two miles south of downtown San Miguel, and primarily serves Carnival and Royal Caribbean Cruise Line ships. If too many ships arrive the same day (occasionally in “high season”), some may moor offshore and tender passengers to docks downtown.