The Cheapest Months to Fly: What a Year of Fares on 12 Routes Reveals
How much more do you pay to fly in peak season? We tracked the lowest round-trip fares month by month on 12 popular routes worldwide. Peak months cost up to twice as much, and the peak isn't always summer.
Everyone knows flying in summer costs more. But how much more, exactly? And is summer really the most expensive time everywhere?
We tracked the lowest round-trip fares month by month, for a full year, on 12 popular routes across Europe, North America, the Middle East and Asia. The differences are bigger than most travelers expect, and the most expensive month isn't always the one you'd guess.
What a year of fares shows
For each route, the table shows the cheapest and the priciest month for a round trip, and how much more the priciest month cost:
| Route | Cheapest month | Priciest month | Peak costs |
|---|---|---|---|
| Paris → Lisbon | January, $89 | April, $189 | 112% more |
| Madrid → New York | February, $293 | June, $603 | 106% more |
| New York → London | February, $404 | June, $801 | 98% more |
| Dubai → London | November, $329 | April, $602 | 83% more |
| New York → Rome | March, $414 | June, $741 | 79% more |
| Istanbul → London | February, $145 | September, $259 | 79% more |
| London → New York | February, $406 | July, $715 | 76% more |
| New York → Lisbon | April, $475 | September, $776 | 63% more |
| London → Tokyo | November, $640 | April, $986 | 54% more |
| London → Dubai | December, $367 | June, $509 | 39% more |
| Frankfurt → New York | January, $454 | July, $617 | 36% more |
| London → Bangkok | November, $505 | April, $673 | 33% more |
How we got these numbers. They are the lowest round-trip fares in the TravelFlow price calendar for trips lasting 7 to 14 days, month by month from November 2026 to October 2027, as recorded on November 2, 2026. Some months had no recent fares on some routes, so each route's cheapest and priciest month is among the months with data. These prices come from recent searches by other travelers, so treat them as a guide to price levels, not guaranteed fares.
What do these numbers tell us?
- Late winter is the sweet spot for flights across the Atlantic: February was the cheapest month from New York to London, from London to New York and from Madrid to New York. From New York to London, June cost almost twice as much.
- Summer is the usual peak, but not the only one: June to September was the priciest period on 8 routes. On the other 4, the peak came in April: London to Tokyo, around cherry blossom season, and Paris to Lisbon, during the spring holidays.
- Direction matters: from London to Dubai, June was the most expensive month; from Dubai to London, it was April. The same route can have different peaks depending on who is traveling where.
- "Shoulder season" isn't automatic: September was still among the priciest months from Istanbul to London and from New York to Lisbon. Always check the actual fares rather than assuming autumn is cheap.
See the seasons on one route
The calendar below shows a full year of fares from New York to Rome. Notice the jump from spring to summer, then change the cities from the settings icon to check your own route:
Prices are based on recent searches and may change. You always see the final price on the seller’s website before you pay.
How to make the most of off-peak months
- Find your route's own peak: it depends on your destination's weather, festivals and school holidays, and on where you're flying from. A price calendar shows it at a glance.
- Consider late winter and early spring: on most of our routes, February and March were among the cheapest months, with milder weather than midwinter in many places.
- Weigh price against weather: the cheapest month at a beach destination may be its rainy season. A slightly pricier month with better weather can be worth it.
- If you must travel in peak season, book early: the cheapest seats go first, as we explain in when to book flights for the lowest fares.
- Be flexible within the month: even in peak season, flying midweek or moving your trip by a few days can lower the price.
- Compare airports too: where a city has several airports, the cheapest one can save you as much as changing the month. See which London airport is cheapest.
The bottom line
On the routes we tracked, choosing the right month mattered more than almost any other trick: the same round trip could cost twice as much in peak season. If your dates are flexible, start with the calendar, find the cheapest month for your route, and plan your trip around it.
Frequently asked questions
What is the cheapest month to fly?
It depends on the route, but in our data the cheapest month fell between November and March on 11 of the 12 routes we tracked. February was the cheapest on four of them, including New York to London and Madrid to New York.
Is summer always the most expensive time to fly?
Often, but not always. The priciest month fell between June and September on 8 of our 12 routes. On the other 4, the peak came in April, including London to Tokyo, which peaks around cherry blossom season.
How much more does peak season cost?
On the routes we tracked, the priciest month cost between 33% and 112% more than the cheapest. From New York to London, a round trip started at $404 in February and $801 in June.
What is shoulder season?
The months just before and after a destination's peak season, when fares and crowds start to drop. Check the actual fares, though, because on several routes in our data September was still almost as expensive as summer.
Does the cheapest month depend on where I fly from?
Yes. Peaks often differ by direction. From London to Dubai, June was the priciest month, while from Dubai to London it was April.
