Open any flight search tool and look at a calendar view for a transatlantic trip. The prices jump around more than most people expect, and a single week can change the fare by hundreds of dollars. The month you pick often matters more than any booking trick.
Different trackers don’t always agree on which month wins. Some name January, some February, and a few point to October or November. The numbers below come from fare sites, airline data and booking analyses published mostly in 2026, and they’re written from the point of view of travelers leaving the United States.
January and February Lead Most Fare Trackers
When fare sites rank the months, winter usually comes out on top. Kayak lists January as the cheapest month for flights from the United States to Europe, with return tickets averaging $587.[1] Momondo names February as the cheapest month to fly from the United States to Europe.[2]
Momondo adds that January is also a cheap choice if February doesn’t work.[2] A separate 2026 guide reaches the same conclusion, saying January and February are the cheapest months, while June through August and December are best avoided.[3] If you want one answer, January or February is the safest.
Why Winter Fares Drop
It comes down to demand. Fewer people want to cross the Atlantic after the holidays, and airlines drop prices to fill seats. One roundup puts the cheapest stretch at January through March, with March averaging around $686 roundtrip, and says the drop comes from supply and demand rather than special promotions.[4]
Don’t confuse the cheapest month to fly with the cheapest month to book. For US to Europe trips, one 2026 analysis says late January through mid March is the cheapest time to book flights for late April through early June travel.[5] That’s a different strategy aimed at spring departures.
March Keeps Winter Prices Going
March is the month where weather starts to improve without fares fully catching up. Its roundtrip average of about $686 still sits well below summer levels.[4] You get slightly longer days and fewer crowds than in peak season.
Southern Europe tends to be the beneficiary. Coverage of 2026 travel notes that as southern Europe shakes off the winter chill, prices stay firmly in low season territory in March.[6] Cities like Lisbon, Rome and Barcelona are workable choices, though a rain jacket belongs in the bag.
November Is the Overlooked Bargain
Most travelers skip November because it’s cold and gray in many European cities. That’s exactly why fares fall. One travel outlet says November offers some of the deepest discounts, with Barcelona, Madrid, Lisbon, Rome and Paris seeing their lowest air and hotel fares.[4]
Timing within the month matters, though. SkySonar’s May 2026 data shows November averaging $585 with a floor price of $342, but notes that holiday traffic pushes prices up mid month.[7] Another analysis flags a Thanksgiving departure spike in late November.[5] Early November departures are the better bet.
What October Data Shows
Not every dataset puts winter first. SkySonar found October to be the cheapest month by average fare, at $364 across the routes it indexes.[7] That figure covers a specific mix of routes, so it isn’t directly comparable to the roundtrip averages from Kayak or momondo.
SkySonar also described 2026 as a favorable year for buyers. It reported that transatlantic seat capacity was up about two percent while US to Europe booking demand was down sharply on several routes.[7] That kind of imbalance tends to help fares, though it can shift from one season to the next.
Shoulder Season as the Middle Path
Not everyone wants to visit Europe in January. Shoulder season offers a compromise between weather and price. The cheaper stretches run from April to early June and again from late August to early October, with flight and hotel prices 20 to 30 percent lower than in summer, according to the European Travel Commission.[4]
Other 2026 guides back this up with slightly different numbers. One says April and May, along with September and October, can run up to 30 percent below the July and August peaks.[8] May and September are the easiest months to recommend if you want decent weather and a lower fare.
Summer Costs the Most
Peak season is easy to define. Europe peaks from June through August, during the summer holidays.[5] Fares reflect that, and so do hotels.
The gap on a single route can be large. One analysis puts a typical New York to London roundtrip at $480 to $650 in shoulder season versus $900 to $1,300 in peak summer.[5] SkySonar’s data lists August with an average roundtrip fare of $944.[7] Cheap summer tickets do exist, but they’re the exception.
How Far Ahead to Book
Booking early doesn’t always win. Google’s October 2026 analysis of five years of US departure data found trips to Europe historically hit their lowest average prices around 90 days before departure, though the lower price window began around 49 days out.[9] That suggests a range of roughly one to three months rather than one magic date.
Other sources differ. Expedia’s 2026 Air Hacks Report says international trips are about $190 cheaper when booked 31 to 45 days in advance.[10] Kayak’s data suggests booking 26 weeks before departure for the absolute lowest price.[1] Expedia’s US data shows the 180 plus day window as the most expensive for both domestic and international tickets.[11]
Which Days of the Week Help
Your departure and return days can move the price more than the day you click buy. Google’s 2026 analysis found that flying out on Monday and returning on Tuesday or Wednesday saved about 14 percent compared with weekend flights.[9] That’s a bigger effect than most booking day tips offer.
The old Tuesday rule has lost ground. Google found Wednesday was the cheapest booking day, but only about 1.4 percent below Sunday.[9] Expedia’s 2026 report names Friday as the cheapest day to book, roughly three percent below Sunday.[10] No day is reliably cheapest.[11]
Time of Day and Airport Choices
Even the hour of departure shows up in the fare data. Kayak reports that afternoon flights to Europe average $739 roundtrip, while night flights, the peak travel time, average $802.[1] The difference isn’t huge, but it adds up for a family.
Arrival airport matters too. Kayak’s data points to London Gatwick as generally the cheapest airport to fly into in Europe, with an average flight price of $281.[1] Departure airport changes the picture, so checking nearby airports and secondary European cities on a fare calendar is worth the extra few minutes.
