Icelandair St. Louis-Keflavík flights: 2027 route guide

Icelandair plans to open the first nonstop link between St. Louis and Iceland on May 14, 2027. The seasonal service will run from St. Louis Lambert International Airport (STL) to Keflavík International Airport (KEF) up to four times a week through October 24.

The route creates two different trip options: a nonstop Iceland holiday or a one-stop journey to Europe through Icelandair's Keflavík hub. Neither the departure times nor flight numbers appeared in the launch announcement, so do not build a separate ticket or fixed event around a time copied from an unofficial schedule.

*Original AI-generated OpenSim editorial illustration. The unbranded aircraft and blended landscape do not show an actual Icelandair flight or a real view along the route.*

The practical answer: The announced operating days are Monday, Wednesday, Friday and Sunday, using a Boeing 737 MAX 8. Service is seasonal and described as “up to” four flights a week, so confirm the exact date, nonstop routing and full itinerary in Icelandair's booking flow before paying for non-refundable plans.

This guide was checked on October 8, 2026, the day after the route was announced.

The announced St. Louis-Iceland schedule

The official St. Louis airport announcement gives the route's current boundaries.

“Up to four” matters. It does not promise four flights in every calendar week, and a seasonal route offers fewer recovery options than a daily service. Search the exact outbound and return dates together. If the nonstop is unavailable, check whether the result has changed to a connection before paying.

Local reports from St. Louis Public Radio and First Alert 4 independently reported the new service. The airport announcement remains the primary source for the season, operating pattern and aircraft.

Decide whether to stop in Iceland or connect onward

Keflavík can be the destination or the connection point. Icelandair says the route will connect St. Louis with more than 35 European destinations, but that network statement does not mean every destination connects cleanly on every STL operating day.

For an Iceland trip, plan the transfer from KEF rather than treating the airport as Reykjavík. Icelandair's airport guidance places KEF about 50 kilometres from the capital. Keflavík Airport's current transport page lists Flybus services to Reykjavík's BSÍ terminal after arriving flights, regular public transport, taxis available around the clock and on-airport rental companies.

For an onward trip, compare the through itinerary with other routings on the same dates. Look at the full elapsed time, connection length, arrival airport and what happens if the STL flight changes. A protected itinerary sold as one booking gives the operating airlines a clearer recovery obligation than two unrelated tickets. It does not guarantee that disruption will be painless.

Know how a Keflavík connection works

Icelandair's KEF connection guide says passengers from the United States generally arrive through the D gates on level 1, while many onward European flights use A or C gates on level 2. The walk can take about 20 minutes. Gate information and border processing still vary by journey, so follow airport signs and live displays.

On a single Icelandair booking, checked bags are generally transferred to the final destination. Collecting a bag is normally required when Iceland is the stopover destination or when the onward flight leaves Reykjavík Domestic Airport (RKV), a different airport reached by ground transport. Separate tickets can also require collection and recheck even when both flights use KEF. The bag tag issued at STL is the trip-specific answer.

A connection time that appears in the airline's own through-booking flow has been constructed for that itinerary, but it leaves no room for sightseeing. Icelandair says gates can begin boarding 70 to 90 minutes before departure. If you want to leave the airport, book a planned stopover rather than treating an ordinary connection as spare city time.

Use the Southwest partnership carefully

The launch announcement also expands Icelandair's partnership with Southwest, the largest carrier at STL. That should create bookable journeys from more US cities through St. Louis to Iceland and Europe. Availability, bag handling and rebooking protection depend on the itinerary actually sold; proximity between two flights is not proof that they are one protected booking.

Southwest's Icelandair partnership page says an eligible itinerary containing a Southwest segment can be booked through Icelandair or an authorized travel agency. It also says Rapid Rewards points are earned only on the Southwest-operated portion, not the Icelandair flight. Add the Rapid Rewards number before travel if earning on the Southwest segment matters.

Before paying, check that every segment appears under the same reservation, then review the baggage allowance for the complete journey. Interline handling does not make the two airlines' fare products identical.

Check the fare, bags and airport details again

The 737 MAX 8 is the announced aircraft, not a promise for every departure. Aircraft, seat maps and schedules can change before a May 2027 launch. Use the operating-airline and aircraft fields shown for the date you are buying.

Icelandair's baggage allowance varies by fare and cabin. Open the bag section of the exact reservation instead of assuming that a checked bag, seat choice or meal is included. Keep medication, identification, batteries and essentials in the smaller item that stays with you if a cabin bag is checked at the gate.

Icelandair's current check-in guidance opens online check-in 24 hours before departure. International travel can still require a document check or bag desk. Recheck the terminal and recommended arrival time with Icelandair and STL close to departure because the route has not begun operating.

On the St. Louis side, MetroLink, taxis, rideshare, hotel shuttles and rental cars are among the options listed on the airport's transportation page. Save the booking and transfer instructions offline before leaving home.

Mobile data for Iceland and onward travel

A live Iceland OpenSim eSIM can provide ground-based mobile data on a compatible unlocked phone after arrival. It can help with airport-bus tickets, maps, accommodation messages and weather checks. A Europe OpenSim eSIM may be a better fit when the trip continues across several countries included by the selected package. Travelers arriving in St. Louis can compare a United States OpenSim eSIM.

OpenSim's public catalog was checked on October 8 and included plans for all three destinations. Prices, allowances, networks, hotspot support and top-up eligibility vary by package and can change. Read the selected card before checkout. An eSIM supplies ground mobile data; it does not provide inflight Wi-Fi, speed up immigration or protect a flight connection.

Ten questions about Icelandair's St. Louis flights

When do Icelandair's St. Louis-Keflavík flights start and end?

The announced season runs from May 14 through October 24, 2027. This is a future seasonal route, so confirm that the chosen flight is on sale and still operating before paying for separate arrangements.

Which days will the STL-KEF nonstop operate?

The published pattern is Monday, Wednesday, Friday and Sunday, up to four times a week. Search both directions for the exact dates because “up to” allows variation.

Will Icelandair fly the route every day?

No. The announcement describes a maximum of four weekly flights. A date outside the pattern may return no flight or a different connecting itinerary.

What are the flight times and flight numbers?

The launch release did not publish them. Treat times shown by a booking engine as date-specific and recheck them before arranging a positioning flight, airport pickup or event.

What aircraft will fly from St. Louis to Iceland?

Icelandair announced a Boeing 737 MAX 8. Check the aircraft and seat map on the live reservation because assignments can change before departure.

Can I book a Southwest connection onto Icelandair at STL?

The expanded partnership is intended to support connections through St. Louis. Buy an itinerary that explicitly includes both segments under the same booking rather than assuming two separately found flights will connect or transfer bags.

Do I collect checked baggage during a KEF connection?

On one Icelandair booking, bags are generally checked through. A stopover in Iceland, an onward domestic flight from Reykjavík Airport or separate tickets can require collection and recheck. Read the tag at STL and ask the check-in agent if it is unclear.

How much connecting time should I allow at Keflavík?

There is no useful single number for every journey. Border processing, gates, mobility and separate tickets change the answer. Prefer the through itinerary Icelandair sells, know that some gates are roughly a 20-minute walk apart, and avoid adding a self-transfer to a short connection.

Can I visit Reykjavík during a connection?

Do not treat a normal connection as a city visit. KEF is outside Reykjavík and ground travel consumes time in both directions. Choose a planned Iceland stopover or overnight stay if leaving the airport is part of the trip.

Should I choose an Iceland or Europe eSIM for this journey?

Choose an Iceland plan for a trip contained in Iceland. Compare a Europe plan when the itinerary continues to multiple covered European countries. Coverage, validity, data and top-up rules come from the selected package, not the route name.

Before booking

• Search the complete May 14-October 24 window for the exact travel dates.
• Confirm that the result says nonstop between STL and KEF.
• Check the Monday, Wednesday, Friday or Sunday operating pattern.
• Read the live times, flight numbers, aircraft and operated-by line.
• Keep a recovery buffer around fixed events and separate tickets.
• Verify whether Southwest and Icelandair segments are on one booking.
• Review the fare's bags, seats, changes and cancellation terms.
• Decide whether Iceland is the destination, a planned stopover or a connection.
• Arrange the KEF-Reykjavík transfer if staying in the capital.
• Recheck passport and destination entry rules before travel.

What to recheck before the route starts

The St. Louis airport release supplied the start and end dates, operating days, maximum frequency, aircraft and partnership expansion. Current Icelandair, Southwest, STL and KEF guidance supplied the connection, rewards, check-in, baggage and ground-transport boundaries. Local reporting was used to corroborate the route announcement, not to fill missing schedule details.

Public traveler discussions were used to identify recurring questions about KEF connection time, immigration, checked bags, separate tickets and leaving the airport. They were not used as evidence for current airline or airport policy.

*Airline, airport, partnership and OpenSim catalog details were checked on October 8, 2026. Update this guide when Icelandair publishes the timetable and flight numbers, opens or changes inventory, starts service, or materially changes the season, frequency, aircraft, baggage, check-in, connection or route status.*