London to Bangkok, June 2026. British Airways nonstop from Heathrow: £1,213 return. THAI nonstop from Heathrow: £1,009. Saudia via Jeddah: £421. Etihad via Abu Dhabi: £577. Qatar Airways via Doha: £611.
The cheapest connecting flight costs 58% less than the cheapest direct. That’s not a sale. It’s structural.
The hub problem
Saudia doesn’t just fly London–Jeddah. It flies Manchester–Jeddah, Paris–Jeddah, Frankfurt–Jeddah — dozens of European cities feeding passengers into one hub. From that hub, it flies Jeddah–Bangkok, Jeddah–Delhi, Jeddah–Tokyo, Jeddah–Jakarta — dozens of long-haul routes fanning out the other side.
The maths: a nonstop London–Bangkok flight needs to fill 300 seats from one city. A connecting route via Jeddah fills those same 300 Bangkok-bound seats from twenty European cities. Each feeder city only needs to contribute 15 passengers, not 300.
Lower risk per route. Higher average load factor — the percentage of seats that actually sell. Lower breakeven price per seat.
Why the airline prices it lower
An airline seat has a bizarre cost structure. The marginal cost of one extra passenger — fuel, food, handling — is roughly £30–60 on a long-haul flight. Everything else (crew, aircraft lease, landing fees, ground ops) is fixed whether the seat is full or empty.
This means an empty seat is pure loss. A seat sold at £421 still contributes £360+ above marginal cost toward those fixed costs. A seat unsold contributes nothing.
Hub carriers would rather sell a connecting seat at £421 than leave it empty waiting for a £1,009 nonstop passenger who might not come. The connecting passenger is lower-yield but higher-certainty.
How the price gets set
Airlines don’t price connecting flights manually. They use what the industry calls “O&D pricing” — origin and destination. Two forces compress the connecting price:
Competition on the city pair. London–Bangkok has BA nonstop, THAI nonstop, EVA Air nonstop, and five hub carriers competing via Jeddah, Abu Dhabi, Doha, Dubai, and Bahrain. More carriers = lower prices.
Demand elasticity. Business travellers pay for nonstop. Leisure travellers accept a connection for the saving. Airlines price-discriminate accordingly — £1,213 for 11 hours 50 minutes nonstop, or £421 for 19 hours 55 minutes with a stop. Same destination, same week, different passenger.
Why hubs can go even lower
A connecting passenger contributes revenue to two flight segments. The Jeddah–Bangkok leg gets partial revenue from the London passenger AND from the Paris passenger AND from the Frankfurt passenger. Shared contribution means a lower price needed per person.
Airlines aim for 80–85% load factor. Below that, yield management — the automated pricing system that adjusts fares based on how fast seats are selling — drops prices on connecting itineraries to pull demand from the leisure segment.
When direct is actually cheaper
It happens. Three scenarios:
Low-cost carrier on the direct route. If Ryanair or Wizz Air flies your city pair direct, no hub carrier can compete on price. Ryanair regularly sells London–Lisbon for under £30 in off-peak months — no connection beats that.
Short-haul where the connection adds too much time. London–Amsterdam direct is about an hour. Fares start around £50–70 return. Connecting via anywhere would cost more in airport taxes alone than you’d save on the airfare.
Oversupplied direct routes in off-peak. London–New York in January sometimes drops below connecting alternatives because every carrier dumps capacity on the route and competes directly for the same leisure demand.
How to find these routes
The practical application: when you’re searching for flights, checking hub connections explicitly often surfaces prices invisible to direct-only searches.
On the London–Bangkok search, five Gulf and Middle Eastern hubs offered connections between £421 and £689 — every one of them cheaper than the cheapest nonstop at £1,009. The hubs: Jeddah (Saudia), Abu Dhabi (Etihad), Bahrain (Gulf Air), Doha (Qatar Airways), Dubai (Emirates).
The pattern: pick your destination, identify which hubs have strong long-haul service there, then search the connection explicitly. A 2–4 hour layover in a well-run hub costs you time but saves you money that the economics structurally guarantee.
The system underneath
Hub-and-spoke isn’t a workaround. It’s the dominant architecture of global aviation because the mathematics of filling planes favour aggregation over point-to-point. Every hub carrier in the world — Saudia, Emirates, Qatar, Etihad, KLM, Lufthansa — exists because this arithmetic works.
The cheaper connecting flight isn’t an anomaly to exploit. It’s the system working as designed.