Buy now or wait on your flight?

The right decision does not come from a prediction, it comes from a point of comparison. "Is now the right time to book?" has no answer in the abstract — but it has one as soon as you know what this flight usually costs, where you are in the booking window, and what each kind of mistake costs you.

Here is the method, without the crystal ball.

Why a price alone means nothing

"$650 for Montreal → Lisbon." Good deal or not?

The question cannot be answered as posed. $650 is excellent if the route normally runs at $850. It is expensive if it drops to $480 twice a year. The number on screen carries no information until it is measured against something.

That is the first habit to build: never judge a price, always judge a gap.

Benchmark 1 — The route's median

Record a route's price over several weeks and a central value emerges: the trip's "normal" price, the one paid most of the time.

That median is your reference. An offer 20% below it is a real drop. An offer above it has no claim on your urgency, however red the banner.

The trap to avoid: comparing to yesterday's price instead of the median. A flight down from $900 to $820 has "dropped 9%" and is still expensive if the route is worth $700.

Benchmark 2 — Where you are in the window

A fare does not read the same way seven months out and three weeks out.

Very early, only the middle fare bands are open: you rarely see the floor, and waiting makes sense. In the final two months the customer mix changes and low bands disappear — waiting becomes a steadily worse bet.

None of this is mysterious; it is described in how airlines set their prices. Take one thing from it: your room to manoeuvre closes, it does not open.

Benchmark 3 — The route's season, not the season in general

"High season" means nothing out of context. August is expensive to Europe and ordinary to South America. March is quiet to Paris and packed to Florida.

What matters is your route's rhythm. A route that doubles in July does not play like a business link that is stable all year.

The asymmetry almost nobody calculates

Here is the point that should decide for you.

You buy too early: the price then falls $60. You lost $60.

You wait too long: the low band closes and the fare goes from $640 to $890. You lost $250 — or the trip, if the budget does not stretch.

The two mistakes do not cost the same. Missing a rise costs structurally more than missing a drop, because fares climb in steps and fall by exception. Hunting the absolute floor is a bet with a small upside and a large downside.

The practical consequence: when an offer moves clearly below its route's median, take it. The theoretical floor is not your target.

When to buy immediately

• The price is markedly below the median for that route.
• You are under two months from departure.
• Your dates are fixed: you have no fallback lever.
• You are travelling as a group: four seats in a low band is a rare event.

When waiting makes sense

• You are more than four months out and the price sits above the median.
• Your dates are flexible by a few days.
• The route is heavily served: competition reopens bands regularly.
• The flight is filling slowly — airlines then correct downwards.

What nobody can promise you

Be wary of tools that attach an accuracy percentage to a prediction. Airfares depend on closed systems recalculating continuously, on unforeseeable events, and on competitors' decisions taken the same morning.

The honest approach is not to guess the future. It is to give you the context — median, gap, position in the window — and let you decide with the right information in hand.

What Kestrelia does with this

Kestrelia builds a history for every monitored route and compares each offer to that usual level rather than to yesterday's price. The saving displayed is therefore a measured gap, not a decorative percentage.

What the tool does not do, and does not claim to: tell you what the price will be next week.

To turn this method into real monitoring, see how to set a price threshold that means something. And if you are still wondering which day to buy, the Tuesday myth answers beside the question — deliberately.