Booking the moment your vacation is approved feels responsible. Our numbers say it often isn't the cheapest move. For the trips we tracked out of Toronto, prices were highest three to four months before departure and lowest in the three to eight weeks before.
We followed 430 specific trips, the same flight dates every time, and recorded their price every day for up to 60 days. That gave us more than 25,000 prices, each tied to how far away the departure was on the day we saw it. Here's how the price of the same trip moved as the date got closer.
Price of the same trip, by how far ahead you book
| Days before departure | Price vs. that trip's typical price |
|---|---|
| 6 months or more | +2.9% |
| 4 to 6 months | +0.8% |
| 3 to 4 months | +3.1% |
| 2 to 3 months | −0.1% |
| 6 to 8 weeks | −2.3% |
| 4 to 6 weeks | −2.1% |
| 3 to 4 weeks | −2.0% |
| 2 to 3 weeks | −1.0% |
| 1 to 2 weeks | +0.7% |
What this means (and what it doesn't)
The window from about three weeks to two months out was the cheapest. That lines up with how airlines manage seats. Early on, they have no reason to discount: the plane is empty and there's plenty of time to sell it. As departure gets closer, they have a much better idea of which flights are going to leave with empty seats, and those are the ones that get cheaper.
But the swing is smaller than people think. From the most expensive window to the cheapest, the difference averaged about 5%. On a $500 fare, that's $25. Picking the right day of the week saves more than that: our separate look at 68,000 fares found that flying home on a Wednesday instead of a Saturday saves about 11%. And the month you travel matters more still.
The last week isn't a bargain bin either. The idea that airlines dump unsold seats at the last minute mostly isn't true for regular economy fares. In our data, prices in the final two weeks drifted back up to average, and for popular routes they usually go higher.
When booking early is still the right call
- Holidays and school breaks. Christmas, March Break and long weekends sell out, and the cheap seats go first. Book those as soon as your dates are firm.
- Small planes and rare routes. If a route only has one or two flights a week, there's no "wait for a discount." Seats just disappear.
- Groups. Four people need four seats in the same fare class. Waiting can mean the family pays two different prices, or doesn't sit together.
- You'd lose sleep over it. Saving $25 isn't worth two months of checking prices every morning.
A simple plan
- Three months out: start watching the price. Don't panic-buy.
- Two months to three weeks out: this is the window. When the price drops below what you've seen, book it.
- Inside two weeks: if you haven't booked, book now. Waiting longer rarely helps.
How we got these numbers. OddFare records flight prices out of Toronto Pearson every day. For this piece we used 430 round-trip itineraries, each with at least 20 days of recorded prices over a 60-day window, from July to September 2026: 25,525 prices in all. Each price is compared with its own trip's median, so a cheap domestic flight and an expensive long-haul one count equally. It's a two-month look, not a decade of history, and holiday periods behave differently, as noted above.
Don't want to watch prices yourself? OddFare flags round trips from Toronto that drop well below their usual price. See today's deals.