When to book — what the data actually says
There is a small industry built around answering "when should I book?" with a single number. The honest answer is that the question is malformed — the booking curve looks different for short-haul domestic, long-haul leisure, and last-minute business — but two patterns survive almost every dataset we look at.
The 6–8 week window for international leisure
For trans-Atlantic and trans-Pacific economy fares, prices tend to bottom out roughly 6 to 8 weeks before departure. Earlier than that and you are paying a "planning premium." Later and you are paying the demand curve.
The 2-week edge for domestic and intra-EU
Short-haul behaves differently. Domestic US and intra-EU fares usually have a soft floor around 14 days out, then climb sharply in the final week. The exception: routes with low-cost-carrier competition, where the floor can creep closer to departure.
What this doesn't tell you
Averages hide the alerts. The 30% discount you actually want shows up in a 6-hour window, not a 6-week one — which is why the question is better framed as "when does the price for my route actually drop?" instead of "when should I book?".
That's a different problem, and a more useful one.
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