Most advice about finding cheap flights is actually advice about finding flights. It tells you where to search, which comparison sites to use, and how to be flexible with dates. All reasonable. None of it answers the real question: how do you know whether the price you're looking at is actually good?

That's the problem worth solving. And it's different from the search problem.

The Alert Fatigue Problem

Free flight alert tools — Google Flights, Skyscanner, airline apps — work by notifying you whenever a fare you're watching drops. That sounds useful. In practice, it means you receive alerts whenever anything changes: a $30 shift on a $1,600 fare, a Tuesday-only pricing quirk, a dip that lasts four hours and reverses. The alerts are technically accurate and practically useless.

There's a structural reason for this. Free tools earn from engagement — clicks, searches, ad impressions. A tool that alerts less frequently isn't meeting its engagement goals. So the threshold for "alert-worthy" stays low, and your inbox fills with notifications that require you to do the analysis the tool should have done for you: is this price actually good?

The question that matters: Not "has the price dropped?" but "is this price cheap by the historical standards of this route?" A fare that's down $60 from last week might still be $300 above where the route sat for three months this time last year. That's not a deal — that's noise.

What "Actually Cheap" Means

A flight fare is genuinely cheap when it's low relative to that route's own price history — not relative to yesterday, or to an arbitrary comparison date, but to the full distribution of prices that route has actually traded at over the past several months.

Every route has a floor and a ceiling. Sydney to London, for example, typically trades between roughly AUD $1,200 and $2,800 in economy. But within that range, there's a meaningful pattern: a set of prices the route hits frequently (the "normal" range), a median price that represents the middle of the market, and occasional lows that represent genuine deals. A fare in the bottom 20% of what that route has historically offered is worth acting on. A fare in the middle of the range, regardless of how it moved in the last 48 hours, is not.

This is the distinction that requires data to make. You can't know whether a price is historically cheap by checking it today — you need months of market history for that specific route to tell you where the current price sits.

Two Types of Deal Worth Catching

Once you understand what "actually cheap" means, two distinct patterns become worth monitoring:

Flash sales

Airlines periodically release promotional fares that sit well below the normal market price — sometimes 30–40% below the median. These aren't errors or glitches; they're deliberate promotions to fill slow periods or new routes, and they're real deals. The problem is they typically last 48–72 hours and aren't announced in advance. By the time a deal surfaces on a deal-sharing forum, the best seats are usually gone.

Historic lows

Occasionally — due to competitive pressure, seasonal patterns, or airline capacity changes — a fare drops to a level it genuinely hasn't been at for months. This isn't a flash sale that reverses in two days; it's a structural repricing of the route. These are the most reliable deals to act on, because the evidence that the price is genuinely low is in the data itself.

Practical Tips That Actually Help

1. Book 6–12 weeks out for international flights

The conventional wisdom is broadly right: the sweet spot for international fares is usually 6 weeks to 3 months before departure. Book earlier than 6 months and most airlines haven't released promotional fares yet. Book within 3 weeks and you're competing for remaining capacity at premium prices. The exception is peak periods (Christmas, July school holidays, cherry blossom season) — those warrant booking 9–12 months out.

2. Be flexible on dates, not just "flexible"

A one-day shift in departure can sometimes move a fare by $100–200 on competitive routes. The most valuable flexibility is around the edges of popular travel periods — departing a week before or after school holidays can be worth several hundred dollars on international fares. Midweek departures (Tuesday/Wednesday) are often marginally cheaper than Friday/Sunday.

3. Compare nearby airports — but be honest about the maths

Alternatives like flying from a different city (for example, checking MEL fares when you're based in Sydney) are occasionally worth considering on highly competitive long-haul routes. But factor in the domestic positioning flight, the time and inconvenience, and baggage check-in requirements. A $150 saving isn't a saving if the domestic flight costs $180 and adds five hours to your travel day.

4. Join airline loyalty programmes — all of them

Joining a frequent flyer programme costs nothing and earns you status benefits, seat upgrades, and occasionally early access to member sales. If you fly Qantas, Singapore Airlines, and Emirates, join all three: you'll earn on every flight and occasionally access member-only promotions that aren't publicly advertised.

5. Act on good fares immediately

Flash sales, in particular, don't wait. A $400 Perth–Bali fare that appears on a Tuesday typically won't be there on Thursday — particularly on routes with smaller seat allocations. The practical implication: if you've identified a fare as genuinely cheap (not just lower than yesterday, but historically low for that route), treat it as time-sensitive. Check it, decide quickly, and book if it meets your criteria.

Why Continuous Monitoring Is the Only Reliable Approach

The logic above leads to an uncomfortable conclusion: you can't catch genuine flight deals by checking prices occasionally. A flash sale that opens on a Tuesday afternoon and closes Thursday isn't catchable on a weekly checking schedule. A historic low that occurs once in a six-month cycle isn't catchable unless you're watching the route continuously.

This is why automated monitoring exists. Not to replace your judgment about whether to book — but to ensure you're seeing the data when a price actually worth your judgment appears.

The key question when choosing a monitoring tool isn't how many routes it covers. It's whether it can tell you when a price is actually cheap — not just cheaper. That requires months of market data for each route, and logic that compares a current fare against that history rather than against yesterday's price.

Know when it's actually cheap.

Flight Monitor compares every fare against that route's own six-month history and alerts you only when the price hits a genuine historic low or a significant flash sale — not on every minor fluctuation. No ads. No booking commissions. The tool works for you, not for airlines.

Start your free 14-day trial

No credit card required · No ads · Cancel anytime

How Flight Monitor Approaches This Differently

Most flight alert tools alert on any price drop. Flight Monitor runs two independent analyses on every route it monitors:

  • Flash sale detection: Is the current market minimum significantly below the route's historic median price? If the route normally trades at $1,600 and the current price is $1,150, that's a flash sale worth knowing about.
  • Historic low detection: Is the current price below the average of the lowest 20% of prices this route has recorded? If yes, the price is cheap by historical standards — not just by the standards of last week.

Both checks run continuously, around the clock. You receive one alert when a real threshold is crossed — not a drip of notifications as prices oscillate by $30 in either direction.

The result is fewer alerts, each of which means something. For a long-haul route where a genuine deal represents AUD $400–600 below the normal fare, a single useful alert typically saves many times the cost of an annual subscription. That's the only metric that matters.

Flight Monitor covers major international carriers from Australian airports. For domestic routes and low-cost carrier-only fares, check airlines directly — we focus on the international market where six-month price history and flash sale detection deliver the clearest signal.