Icelandair will launch St. Louis–Keflavik flights on 14 May 2027, adding a seasonal US gateway as it expands its partnership with Southwest Airlines. The joint announcement was published by St. Louis Lambert International Airport on 7 October.
The service is planned through 24 October using Boeing 737 MAX 8 aircraft, with up to four weekly flights. The announced operating days are Monday, Wednesday, Friday and Sunday.
The connection is the bigger story
Icelandair links the addition to its growing Southwest relationship and access through Iceland to more than 35 European destinations. That gives the route a broader commercial purpose than carrying only passengers travelling between Missouri and Iceland.
For passengers, however, network reach and a workable itinerary are different things. Individual connections depend on the published timings and available booking combinations; the destination count is not a promise of every connection on every operating day.
For airport and ground teams, the next concrete planning reference is the final operating schedule. The announcement confirms an aircraft type, seasonal window and maximum weekly frequency, providing a clearer starting point than a general statement of interest in transatlantic expansion.