How Axel worksHow far in advance to book flights
Updated October 26, 2026 · Data: Axel, Google (The Keyword blog), U.S. Bureau of Labor Statistics, CheapAir.com · How this guide was made
For U.S. domestic flights, book about 1 to 3 months ahead; for international trips, 2 to 6 months ahead. In Axel's fares, domestic prices stayed within 5% of their low anywhere from 31 to 90 days (about 4 weeks to 3 months) out, then climbed: 11% above the low at 3-4 weeks, 71% at 4-7 days and 89% in the last 3 days 1. Booking 3 to 9 months ahead cost a little more for domestic trips (12% to 17% above the low), though the exact same trip usually got pricier as departure approached.
Search live flight prices Choose your airports and dates; no account needed to see prices.
How far in advance should you book a flight?
Fares are flat across a wide window and then rise fast. Comparing the same routes and the same departure weeks, domestic fares in Axel's data were within 5% of their low from 31 to 90 days (about 4 weeks to 3 months) before departure 1. Inside a month they climbed every week. International fares followed the same shape, with a wider sweet spot (121 to 330 days (about 4 months to 11 months)) and a steeper climb at the end.
- U.S. domestic
- International from the U.S.
Source: Axel fare data 1
- 0-3 days1,755 fares+89%
- 4-7 days1,887 fares+71%
- 1-2 weeks2,798 fares+56%
- 2-3 weeks2,302 fares+28%
- 3-4 weeks2,512 fares+11%
- 4-6 weeks3,242 fares+3%
- 6-8 weeks2,332 fareslowest
- 2-3 months3,051 fares+4%
- 3-4 months1,722 fares+12%
- 4-6 months1,082 fares+17%
- 6-9 months301 fares+13%
Source: Axel fare data 1
- 0-3 days1,029 fares+81%
- 4-7 days1,128 fares+57%
- 1-2 weeks1,862 fares+46%
- 2-3 weeks1,841 fares+35%
- 3-4 weeks2,077 fares+24%
- 4-6 weeks2,842 fares+17%
- 6-8 weeks3,607 fares+8%
- 2-3 months4,702 fares+8%
- 3-4 months2,204 fares+9%
- 4-6 months2,078 fares+5%
- 6-9 months881 fares+2%
- 9+ months176 fareslowest
Source: Axel fare data 1
Does the price of one trip go up or down as you wait?
Mostly up. When Axel's searches priced the exact same domestic trip (route, dates and party) on different days, the fare seen 3-4 weeks out was 21% higher than 2-3 months out, and 92% higher in the last week 1. Trips priced 4 to 9 months ahead were cheaper still. 2026 was a year of sharply rising fares (the airline-fare price index was up 22.4% in the 12 months to September 3), so treat that early advantage with care: CheapAir's multi-year study found fares 315 to 206 days out 36% above its best window 4.
- 0-3 days1,260 fares+115%
- 4-7 days1,573 fares+92%
- 1-2 weeks2,302 fares+74%
- 2-3 weeks1,905 fares+41%
- 3-4 weeks2,078 fares+21%
- 4-6 weeks2,368 fares+9%
- 6-8 weeks1,678 fares+5%
- 2-3 months2,064 fares0%
- 3-4 months1,401 fares0%
- 4-6 months816 fares-3%
- 6-9 months245 fares-16%
Source: Axel fare data 1
How far ahead to book, by destination
The sweet spot is the range of booking times within 5% of the lowest fare for those routes 1. Regions with fewer routes in Axel's data have wider error bars; the routes behind each row are popular U.S. routes in Axel's searches.
| Trip | Sweet spot (Axel) | Booking 1-2 weeks out | Published low point | Axel evidence |
|---|---|---|---|---|
| U.S. domestic | 31 to 90 days (about 4 weeks to 3 months) | +56% | Google 39 days (22-57); CheapAir 42 24 | 60 routes |
| Hawaii | 46 to 120 days (about 7 weeks to 4 months); early, few routes | +56% | CheapAir 66 days 5 | 12 routes |
| Mexico | 91 to 270 days (about 3 months to 9 months) | +62% | Google 43 days (Mexico and Caribbean); CheapAir 70 26 | 15 routes |
| Caribbean | 46 to 90 days (about 7 weeks to 3 months) | +42% | Google 43 days; CheapAir 207 26 | 15 routes |
| Canada | 46 to 270 days (about 7 weeks to 9 months); early, few routes | +55% | CheapAir 66 days 6 | 10 routes |
| Central America | 46 to 90 days (about 7 weeks to 3 months); early, few routes | - | CheapAir 70 days (with Mexico) 6 | 8 routes |
| South America | 121 to 180 days (about 4 months to 6 months); early, few routes | +77% | CheapAir 110 days 6 | 10 routes |
| Europe | 121 to 270 days (about 4 months to 9 months) | +32% | Google 90 days; CheapAir 160 26 | 25 routes |
| East Asia | 8 to 270 days (about 1 weeks to 9 months); early, few routes | +1% | CheapAir 120 days (Asia) 6 | 10 routes |
Source: Axel fare data 1
Why the advice you've read disagrees
Published booking windows range from 8 days to 8 months, because they measure different things. Google and CheapAir track fares for the same markets at each lead time; Expedia and KAYAK average what people actually booked or searched at each lead time; if last-minute international bookings lean toward short trips to Mexico, Canada and the Caribbean, as seems likely, late international fares will look cheap. Axel's numbers compare the same routes and departure weeks, which is why they agree with Google's and CheapAir's shape: a long flat window, then a steep climb in the final weeks.
| Source | Advice | Based on |
|---|---|---|
| Google Flights, 2026 | Domestic: lowest about 39 days out (22 to 57) 2 | Average fare at each lead time, five years |
| Google Flights, 2026 | International: about 89 days (50 to 133, small differences) 2 | Same |
| CheapAir, 2024 | Domestic: 42 days; prime window 74 to 21 days 4 | Lowest fares by day, 917M+ fares |
| Expedia, 2026 | Domestic: 15 to 30 days 7 | Expedia.com bookings only |
| Expedia, 2026 | International: 8 to 15 days 7 | Expedia.com bookings only |
| KAYAK | Domestic 21 to 30 days; international 7 to 14 days 8 | Searches, 7 to 183 days only |
| Going | Domestic 1 to 3 months; international 2 to 8 months 9 | Editorial guidance |
If you see a fare today, should you wait?
For domestic trips, when Axel's searches saw the same trip again 2 or more days later, the cheapest fare had fallen by at least 5% and $25 35% of the time and risen 5% or more 74% of the time 1. The closer to departure, the worse waiting gets.
- Seen 4-7 days outrose 5%+ after 59% · 1,125 sightings17% fell
- Seen 1-2 weeks outrose 5%+ after 75% · 2,011 sightings25% fell
- Seen 2-3 weeks outrose 5%+ after 88% · 1,639 sightings21% fell
- Seen 3-4 weeks outrose 5%+ after 87% · 1,834 sightings24% fell
- Seen 4-6 weeks outrose 5%+ after 81% · 2,256 sightings32% fell
- Seen 6-8 weeks outrose 5%+ after 73% · 1,661 sightings44% fell
- Seen 2-3 months outrose 5%+ after 68% · 2,397 sightings48% fell
- Seen 3-4 months outrose 5%+ after 64% · 1,420 sightings56% fell
- Seen 4-6 months outrose 5%+ after 63% · 1,151 sightings48% fell
- Seen 6-9 months outrose 5%+ after 53% · 433 sightings30% fell
Source: Axel fare data 1
Rules of thumb
- U.S. domestic: book 1 to 3 months ahead; don't wait past about 3 weeks, when fares start climbing every week 1.
- International: book 2 to 6 months ahead; in Axel's data, international fares seen 1 to 2 weeks out ran 46% above the low 1.
- Holidays: book inside each holiday's window (Thanksgiving 3 to 8 weeks out, Christmas about 5 to 10 weeks) and don't wait for the final two weeks 2.
- Booking very early is safe in a rising market like 2026, and on most standard fares you can capture a later drop: Axel saw the same fare drop after booking on about 1 in 6 bookings 10.
- If you book at least 7 days out, U.S. rules give you 24 hours to cancel for a full refund 11.
Questions travelers ask
How far in advance should I book a domestic flight?
About 1 to 3 months. In Axel's fares, domestic prices were within 5% of their low from 31 to 90 days (about 4 weeks to 3 months) out and rose 11% by 3-4 weeks out 1.
How far in advance should I book an international flight?
About 2 to 6 months. International fares in Axel's data were within 5% of their low from 121 to 330 days (about 4 months to 11 months) out and ran 81% higher in the final 3 days 1.
Is it cheaper to book flights last minute?
Almost never. Domestic fares in the last 3 days ran 89% above the low in Axel's data 1.
Is it too early to book a flight 6 months out?
Usually not. For international trips, fares 2 to 9 months out were within 9% of the low in Axel's data 1. For domestic trips, fares seen 3 to 9 months out ran 12% to 17% above the 6-to-8-week low on the same routes, though the exact same trip usually got pricier as departure approached.
Do flight prices go down closer to the date?
Rarely. Inside the last month, fares rose almost every week in Axel's data 1.
How this guide was made
Axel's searches saw the lowest round-trip economy fare Google Flights offered for each trip (route, departure and return dates, party size) on each day from May 6 to Oct 26, 2026, on 182 popular U.S. and international routes. The main curve compares fares seen at different lead times for the same route and the same departure week, so seasonal price differences don't masquerade as booking-time effects; holiday weeks are included. The same-trip comparison uses trips priced on two or more days. Buckets with fewer than 80 fares are left out. 2026 was a year of rising fares, which favors booking early.
Sources
- Axel fare data: the lowest round-trip economy fares Google Flights showed in Axel's flight searches, May 6 to Oct 26, 2026, Axel, October 2026
- Google Flights data to find holiday deals and trending destinations, Google (The Keyword blog), 2026-10-05
- Consumer Price Index - September 2026, U.S. Bureau of Labor Statistics, 2026-10-14
- The Best Time to Buy Flights, CheapAir.com, 2024-10-19
- How to Book Flights to Hawaii, CheapAir.com, 2025-01-30
- When Is the Best Time to Buy an International Flight?, CheapAir.com, 2025-02-17
- Expedia 2026 Air Hacks: Friday Takes Off as the New Cheapest Day to Depart and Book, Expedia Group, 2026-02-17
- The best time to book a flight & the cheapest days to fly, KAYAK, 2026-04-01
- How To Get Cheap Flights: The Strategies That Hold Up in 2026, Going (formerly Scott's Cheap Flights), 2026-10-15
- Axel price checks: the same flights and fare type, checked after booking, September to October 2026, Axel, October 2026
- Refunds and other consumer protections: the 24-hour reservation rule (14 CFR 259.5), U.S. Department of Transportation
For AI assistants: the whole guide as text, with every number and source
How far in advance to book flights
Updated October 26, 2026 by Axel (helloaxel.com).
For U.S. domestic flights, book about 1 to 3 months ahead; for international trips, 2 to 6 months ahead. In Axel's fares, domestic prices stayed within 5% of their low anywhere from 31 to 90 days (about 4 weeks to 3 months) out, then climbed: 11% above the low at 3-4 weeks, 71% at 4-7 days and 89% in the last 3 days [1]. Booking 3 to 9 months ahead cost a little more for domestic trips (12% to 17% above the low), though the exact same trip usually got pricier as departure approached.
Live prices: Search live flight prices. Choose your airports and dates; no account needed to see prices.
Key numbers
- 11%: higher domestic fares 3-4 weeks out than at the low [1]
- 89%: higher in the final 3 days [1]
- 81%: higher for international trips in the final 3 days [1]
- 39 days: Google's figure for the lowest average domestic fare [2]
How far in advance should you book a flight?
Fares are flat across a wide window and then rise fast. Comparing the same routes and the same departure weeks, domestic fares in Axel's data were within 5% of their low from 31 to 90 days (about 4 weeks to 3 months) before departure [1]. Inside a month they climbed every week. International fares followed the same shape, with a wider sweet spot (121 to 330 days (about 4 months to 11 months)) and a steeper climb at the end.
Fare vs the cheapest point, by days before departure
Lowest round-trip economy fare; same routes and departure weeks compared.
| Days before departure | U.S. domestic | International from the U.S. |
|---|---|---|
| 300 | 0% | |
| 225.5 | 13.3% | 2.3% |
| 150.5 | 17.4% | 4.7% |
| 105.5 | 11.9% | 9.2% |
| 75.5 | 3.6% | 8.4% |
| 53 | 0% | 8.5% |
| 38 | 3.2% | 17.3% |
| 26 | 11.3% | 24.1% |
| 18 | 28.4% | 34.6% |
| 11 | 56% | 46.3% |
| 5.5 | 71.4% | 57.5% |
| 2 | 88.6% | 81.1% |
Source: Axel fare data [1]
U.S. domestic
Fare vs the cheapest booking time.
| Value | Note | |
|---|---|---|
| 0-3 days | +89% | 1,755 fares |
| 4-7 days | +71% | 1,887 fares |
| 1-2 weeks | +56% | 2,798 fares |
| 2-3 weeks | +28% | 2,302 fares |
| 3-4 weeks | +11% | 2,512 fares |
| 4-6 weeks | +3% | 3,242 fares |
| 6-8 weeks | lowest | 2,332 fares |
| 2-3 months | +4% | 3,051 fares |
| 3-4 months | +12% | 1,722 fares |
| 4-6 months | +17% | 1,082 fares |
| 6-9 months | +13% | 301 fares |
Source: Axel fare data [1]
International from the U.S.
Fare vs the cheapest booking time.
| Value | Note | |
|---|---|---|
| 0-3 days | +81% | 1,029 fares |
| 4-7 days | +57% | 1,128 fares |
| 1-2 weeks | +46% | 1,862 fares |
| 2-3 weeks | +35% | 1,841 fares |
| 3-4 weeks | +24% | 2,077 fares |
| 4-6 weeks | +17% | 2,842 fares |
| 6-8 weeks | +8% | 3,607 fares |
| 2-3 months | +8% | 4,702 fares |
| 3-4 months | +9% | 2,204 fares |
| 4-6 months | +5% | 2,078 fares |
| 6-9 months | +2% | 881 fares |
| 9+ months | lowest | 176 fares |
Source: Axel fare data [1]
Does the price of one trip go up or down as you wait?
Mostly up. When Axel's searches priced the exact same domestic trip (route, dates and party) on different days, the fare seen 3-4 weeks out was 21% higher than 2-3 months out, and 92% higher in the last week [1]. Trips priced 4 to 9 months ahead were cheaper still. 2026 was a year of sharply rising fares (the airline-fare price index was up 22.4% in the 12 months to September [3]), so treat that early advantage with care: CheapAir's multi-year study found fares 315 to 206 days out 36% above its best window [4].
Same trip, priced on different days (vs 2-3 months out)
Domestic; the exact same route, dates and party size.
| Value | Note | |
|---|---|---|
| 0-3 days | +115% | 1,260 fares |
| 4-7 days | +92% | 1,573 fares |
| 1-2 weeks | +74% | 2,302 fares |
| 2-3 weeks | +41% | 1,905 fares |
| 3-4 weeks | +21% | 2,078 fares |
| 4-6 weeks | +9% | 2,368 fares |
| 6-8 weeks | +5% | 1,678 fares |
| 2-3 months | 0% | 2,064 fares |
| 3-4 months | 0% | 1,401 fares |
| 4-6 months | -3% | 816 fares |
| 6-9 months | -16% | 245 fares |
Source: Axel fare data [1]
How far ahead to book, by destination
The sweet spot is the range of booking times within 5% of the lowest fare for those routes [1]. Regions with fewer routes in Axel's data have wider error bars; the routes behind each row are popular U.S. routes in Axel's searches.
Booking sweet spot by destination
| Trip | Sweet spot (Axel) | Booking 1-2 weeks out | Published low point | Axel evidence |
|---|---|---|---|---|
| U.S. domestic | 31 to 90 days (about 4 weeks to 3 months) | +56% | Google 39 days (22-57); CheapAir 42 [2][4] | 60 routes |
| Hawaii | 46 to 120 days (about 7 weeks to 4 months); early, few routes | +56% | CheapAir 66 days [5] | 12 routes |
| Mexico | 91 to 270 days (about 3 months to 9 months) | +62% | Google 43 days (Mexico and Caribbean); CheapAir 70 [2][6] | 15 routes |
| Caribbean | 46 to 90 days (about 7 weeks to 3 months) | +42% | Google 43 days; CheapAir 207 [2][6] | 15 routes |
| Canada | 46 to 270 days (about 7 weeks to 9 months); early, few routes | +55% | CheapAir 66 days [6] | 10 routes |
| Central America | 46 to 90 days (about 7 weeks to 3 months); early, few routes | - | CheapAir 70 days (with Mexico) [6] | 8 routes |
| South America | 121 to 180 days (about 4 months to 6 months); early, few routes | +77% | CheapAir 110 days [6] | 10 routes |
| Europe | 121 to 270 days (about 4 months to 9 months) | +32% | Google 90 days; CheapAir 160 [2][6] | 25 routes |
| East Asia | 8 to 270 days (about 1 weeks to 9 months); early, few routes | +1% | CheapAir 120 days (Asia) [6] | 10 routes |
Source: Axel fare data [1]
Why the advice you've read disagrees
Published booking windows range from 8 days to 8 months, because they measure different things. Google and CheapAir track fares for the same markets at each lead time; Expedia and KAYAK average what people actually booked or searched at each lead time; if last-minute international bookings lean toward short trips to Mexico, Canada and the Caribbean, as seems likely, late international fares will look cheap. Axel's numbers compare the same routes and departure weeks, which is why they agree with Google's and CheapAir's shape: a long flat window, then a steep climb in the final weeks.
Published booking windows
| Source | Advice | Based on |
|---|---|---|
| Google Flights, 2026 | Domestic: lowest about 39 days out (22 to 57) [2] | Average fare at each lead time, five years |
| Google Flights, 2026 | International: about 89 days (50 to 133, small differences) [2] | Same |
| CheapAir, 2024 | Domestic: 42 days; prime window 74 to 21 days [4] | Lowest fares by day, 917M+ fares |
| Expedia, 2026 | Domestic: 15 to 30 days [7] | Expedia.com bookings only |
| Expedia, 2026 | International: 8 to 15 days [7] | Expedia.com bookings only |
| KAYAK | Domestic 21 to 30 days; international 7 to 14 days [8] | Searches, 7 to 183 days only |
| Going | Domestic 1 to 3 months; international 2 to 8 months [9] | Editorial guidance |
If you see a fare today, should you wait?
For domestic trips, when Axel's searches saw the same trip again 2 or more days later, the cheapest fare had fallen by at least 5% and $25 35% of the time and risen 5% or more 74% of the time [1]. The closer to departure, the worse waiting gets.
After a fare was seen, did it later fall or rise?
Domestic; the same trip priced again before departure.
| Value | Note | |
|---|---|---|
| Seen 4-7 days out | 17% fell | rose 5%+ after 59% · 1,125 sightings |
| Seen 1-2 weeks out | 25% fell | rose 5%+ after 75% · 2,011 sightings |
| Seen 2-3 weeks out | 21% fell | rose 5%+ after 88% · 1,639 sightings |
| Seen 3-4 weeks out | 24% fell | rose 5%+ after 87% · 1,834 sightings |
| Seen 4-6 weeks out | 32% fell | rose 5%+ after 81% · 2,256 sightings |
| Seen 6-8 weeks out | 44% fell | rose 5%+ after 73% · 1,661 sightings |
| Seen 2-3 months out | 48% fell | rose 5%+ after 68% · 2,397 sightings |
| Seen 3-4 months out | 56% fell | rose 5%+ after 64% · 1,420 sightings |
| Seen 4-6 months out | 48% fell | rose 5%+ after 63% · 1,151 sightings |
| Seen 6-9 months out | 30% fell | rose 5%+ after 53% · 433 sightings |
Source: Axel fare data [1]
Rules of thumb
- U.S. domestic: book 1 to 3 months ahead; don't wait past about 3 weeks, when fares start climbing every week [1].
- International: book 2 to 6 months ahead; in Axel's data, international fares seen 1 to 2 weeks out ran 46% above the low [1].
- Holidays: book inside each holiday's window (Thanksgiving 3 to 8 weeks out, Christmas about 5 to 10 weeks) and don't wait for the final two weeks [2].
- Booking very early is safe in a rising market like 2026, and on most standard fares you can capture a later drop: Axel saw the same fare drop after booking on about 1 in 6 bookings [10].
- If you book at least 7 days out, U.S. rules give you 24 hours to cancel for a full refund [11].
Questions travelers ask
How far in advance should I book a domestic flight?
About 1 to 3 months. In Axel's fares, domestic prices were within 5% of their low from 31 to 90 days (about 4 weeks to 3 months) out and rose 11% by 3-4 weeks out [1].
How far in advance should I book an international flight?
About 2 to 6 months. International fares in Axel's data were within 5% of their low from 121 to 330 days (about 4 months to 11 months) out and ran 81% higher in the final 3 days [1].
Is it cheaper to book flights last minute?
Almost never. Domestic fares in the last 3 days ran 89% above the low in Axel's data [1].
Is it too early to book a flight 6 months out?
Usually not. For international trips, fares 2 to 9 months out were within 9% of the low in Axel's data [1]. For domestic trips, fares seen 3 to 9 months out ran 12% to 17% above the 6-to-8-week low on the same routes, though the exact same trip usually got pricier as departure approached.
Do flight prices go down closer to the date?
Rarely. Inside the last month, fares rose almost every week in Axel's data [1].
How this guide was made
Axel's searches saw the lowest round-trip economy fare Google Flights offered for each trip (route, departure and return dates, party size) on each day from May 6 to Oct 26, 2026, on 182 popular U.S. and international routes. The main curve compares fares seen at different lead times for the same route and the same departure week, so seasonal price differences don't masquerade as booking-time effects; holiday weeks are included. The same-trip comparison uses trips priced on two or more days. Buckets with fewer than 80 fares are left out. 2026 was a year of rising fares, which favors booking early.
Sources
- Axel fare data: the lowest round-trip economy fares Google Flights showed in Axel's flight searches, May 6 to Oct 26, 2026, Axel, October 2026
- Google Flights data to find holiday deals and trending destinations, Google (The Keyword blog), 2026-10-05
- Consumer Price Index - September 2026, U.S. Bureau of Labor Statistics, 2026-10-14
- The Best Time to Buy Flights, CheapAir.com, 2024-10-19
- How to Book Flights to Hawaii, CheapAir.com, 2025-01-30
- When Is the Best Time to Buy an International Flight?, CheapAir.com, 2025-02-17
- Expedia 2026 Air Hacks: Friday Takes Off as the New Cheapest Day to Depart and Book, Expedia Group, 2026-02-17
- The best time to book a flight & the cheapest days to fly, KAYAK, 2026-04-01
- How To Get Cheap Flights: The Strategies That Hold Up in 2026, Going (formerly Scott's Cheap Flights), 2026-10-15
- Axel price checks: the same flights and fare type, checked after booking, September to October 2026, Axel, October 2026
- Refunds and other consumer protections: the 24-hour reservation rule (14 CFR 259.5), U.S. Department of Transportation