Airlines use revenue management systems that adjust prices based on demand, load factor and days to departure. The system raises prices as seats fill up and lowers them to fill slow-selling flights.
Your goal is to book during the window when supply is adequate and demand has not yet pushed prices up.
Years of pricing data from fare tracking tools including Google Flights and Kayak produce consistent findings:
| Route Type | Cheapest Booking Window | Avoid |
|---|---|---|
| Domestic short-haul | 3 to 6 weeks before | Same week or same day |
| Short-haul international | 5 to 10 weeks before | Last 2 weeks |
| Long-haul (6 hours or more) | 2 to 5 months before | Last 4 weeks |
| Peak holiday travel | 4 to 7 months before | After school breaks start |
These windows are averages. Individual routes and airlines behave differently. Use the data as a starting point, then set price alerts to track your specific route.
Google Flights offers the most reliable fare alerts at no cost. The process:
Hopper uses AI to predict price movement. It tells you whether to book now or wait. Its predictions are accurate roughly 70% of the time, which is more useful than guessing.
Skyscanner sends email alerts when prices drop below a threshold you set.
Set alerts on at least two platforms for the same route. Different algorithms catch different price drops.
Use the Schedule Finder to identify the cheapest travel dates for your route. Enter your origin, destination and a flexible date range to see which days offer the best combination of timing and price.
Find Best ScheduleCalculate FareFlights departing on Tuesday, Wednesday and Saturday are consistently cheaper than Friday, Sunday and Monday departures. The difference averages 15 to 25% on domestic routes.
The reason is simple: business travellers fly Monday through Friday. Leisure travellers cluster on Friday and Sunday. Mid-week flights carry less demand, so prices drop.
For international routes, the difference between peak and shoulder season fares is often larger than the difference between booking early and booking late.
Example for London to Bangkok:
Travelling two weeks earlier or later than peak dates saves more money than any booking strategy.
Airlines occasionally publish fares far below normal prices due to technical errors or currency conversion mistakes. These fares last between 30 minutes and 24 hours before the airline corrects them.
Sources that track error fares:
When an error fare appears, book immediately and worry about logistics afterward. Airlines generally honour error fares once ticketed, though some have policies that allow cancellation.
Clearing your browser cookies before searching does not reliably lower prices. Airlines do not consistently use search history to raise prices. This is a persistent myth without strong supporting data.
Booking exactly 47 days before departure does not guarantee the cheapest fare. This figure circulated widely but does not hold across routes, airlines and seasons.
The most reliable strategies are: book within the proven window for your route type, use price alerts and travel on low-demand days.