KLM has low fares from Chicago to Athens, Thessaloniki and even a relatively low fare at $702 for Santorini for flights this month. Flights in August price on Google Flights, but show bookings through phone reservations with KLM or a travel agency. I find when Google Flights shows this message I often find the price shown through an OTA site found via Momondo.com. August flights are found through Momondo.com and later dates from September through March 2017 are bookable online at the airline websites.
Both SkyTeam and Star Alliance flights to Athens are priced from $547 to $577 most dates from September through March 17, and even remain under $600 during December holidays with Star Alliance.
Thessaloniki SKG $580 with SkyTeam, but many of these fares look like they are currently repricing higher. Star Alliance is in the $630s and several of the KLM fares I checked have also risen from $580 to $630. Still I did find some dates still under $600 round trip.
Santorini JTR and Mykonos JMK are two of the premier resort islands of the Aegean Sea. KLM has fares at $702 for August departures on some dates. I was unable to get these to book online with KLM, but these low fares are available through online travel agency sites found through Momondo.com searches.
KLM Chicago ORD – New York JFK – Athens, Greece ATH – Amsterdam AMS (17 hr overnight layover)
Swiss Airlines Chicago ORD – Zurich ZRH – Athens ATH – Zurich ZRH – Chicago ORD
Momondo.com OTA meta-search pulls up low August departure fares bookable online.
SmartFares.com KLM Skyteam flights Chicago ORD – Athens ATH
$571.88 round trip Sat Aug 20 – Mon Aug 29
Momondo.com Chicago ORD – Santorini, Greece JTR
$702.17 Travelgenio.com Tue Aug 23 – Fri Sep 2
United even has Athens on sale during the Christmas holiday period.
United Airlines Chicago ORD – Newark EWR – Frankfurt FRA – Athens ATH – Frankfurt FRA – Montreal YUL – Chicago ORD
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