Why flight prices change so much (and so fast)
Last updated: 11 July 2026
You search a flight on Monday: S$380. Wednesday: S$460. Friday: S$395. Nothing about the flight changed — same plane, same seats, same fuel. So what happened? The short answer: you watched an airline's revenue-management system doing its job in real time.
Fare buckets: one cabin, many prices
Airlines don't sell "economy seats" at one price. Each cabin is divided into invisible fare buckets — the same physical seat might exist in a dozen price classes from deep-discount to fully-flexible. When you search, you're shown the cheapest bucket that still has seats. When that bucket sells out, the price "jumps" — really, you're just seeing the next bucket up.
This is also why prices seem to rise while you're searching. It's not your cookies — it's other travellers buying the last seats in the cheap bucket while you hesitate.
Revenue management: the constant re-forecast
Behind the buckets sits a forecasting system that re-estimates demand for every flight, continuously. Selling faster than expected? Close cheap buckets early. Selling slower? Reopen them — that's a "price drop," and it's the moment fare trackers exist to catch. Big inputs include:
- Days to departure — leisure bookings come early and price-sensitive; late bookers are treated as business traffic and charged accordingly.
- Seasonality and events — school holidays, Lunar New Year, cherry blossom, a concert weekend at the destination.
- Competition — a budget carrier adding capacity on a route can drag everyone's cheap buckets open; a competitor cancelling flights does the opposite.
Why this is good news for travellers
Volatile pricing sounds hostile, but it creates the very dips deal-hunters live on. When a forecast misses — a flight selling slower than the airline hoped — cheap buckets reopen, sometimes dramatically. Those windows are usually brief (often under 48 hours) and invisible unless something is watching the route every day.
That's the mechanic FareSteal is built on: we track the cheapest fare on each route daily (see any route page), so when a fare lands well below its tracked normal, it stands out immediately instead of slipping past.
Curious what the buckets are doing today? The live deals page shows the cheapest tracked fares from Singapore right now.