Your best option : pricecomparison website sush as Kayak, AirTickets or Skyscanner.
Up to you to try different dates to obtain the best prices.
Buying your air tickets 5 to 3 months in advance, the price range for a return ticket to Athens will cost you between 200 to 300 euros.
During the season, flights are operated by Aegean Airlines, Air France, Transavia, Alitalia, Volotea or Easyjet.
Outside the high season (from Nov. to Apr) there is no price variation. You will be able to book only through Air France or Alitalia.
**** Beware : no direct flights to Paros for the time being from european cities, you will need to transit through Athens ****
BY PLANE :
Flight duration : 45 minutes (Aegean Airline, Olympic Air and Sky Express),
BY BOAT FROM THE PIREA HARBOUR :
– To reach Pirea Port from the airport, you can take the taxi (50 euros) or take the X96 bus at the terminal exit. It is a direct Express route with Pirea as last stop. It will take you approximately 1 hour to reach the harbour and will cost you 10 euros.
– To reach Pirea Port from the airport, you can take the underground blue #3 line connection Monastiraki Station with the green #1 line to Pirea Port. Cost 10 euros.
Boat to Paros, the crossing will last 3h45 or 2h30 by hydrospeed.
To ease your arrival, you may book your boat tickets directly on Internet with FILIPPIS TOURS or on the BLUE STAR FERRIES website. Tickets will be either sent by post or made available by the port offices.
For July and August, a one month in advance booking is sufficient. Outside these months, booking is unecessary as you will be ablr to buy your tickets directly and the port’s agencies.
Should you wish to stay and visit the center of Athens first, take the X95 bus line.
MAIN LINKS BETWEEN PAROS AND THE OTHER ISLANDS
Different Shipping Compagnies : Blue Star Ferries, Hellenic SeaWays, Sea Jets et Golden Star Ferries.
Amorgos : one to two direct links every day,
Antiparos : several direct links every day from the Pounda village or by caïques from Parikia every hour during the high season.
Ios : one to two links every day,
Le Pirée : around six departures every day,
Mykonos : two to three links every day,
Naxos : five to six links every day, for a 1h30 crossing,
Santorin : around six departures every day, for a 3-hours crossing,
Syros : two to three links every day, for a 3-hours crossing,
Tinos : two departures each day, for a 3-hours crossing.