Stansted, Luton and Gatwick have the cheapest tickets — but once you add baggage and the airport transfer, a more expensive ticket to Heathrow can be cheaper overall.
The cheapest ticket is rarely the cheapest journey. Stansted, Luton and Gatwick have the lowest advertised ticket prices (Ryanair, Wizz Air, easyJet — often £30–60 one-way). But once you add a checked bag (£35–60), an airport transfer (£10–25), and factor in schedule waiting, a more expensive ticket to Heathrow (which is closer to central London and has cheaper transfers) can be cheaper overall. Always compare the complete door-to-door cost — not just the ticket price.
Here is a typical comparison for a European flight with one checked bag to central London:
The budget airline model works by unbundling: the base fare is low, but everything else costs extra. Checked bag: £35–60. Seat selection: £5–25. Airport transfer from a distant airport: £10–25. Schedule waiting: 30–90 minutes of your time. When you add everything up, the 'cheap' ticket can become the expensive journey.
Write down the total cost for both options: ticket + baggage + seat selection + airport transfer (both ends) + any schedule-related costs (hotel, taxi). Only then compare. Or use the Travelvus Comparison Engine — paste both flights and it calculates the real cost automatically for supported routes.
Stansted (Ryanair's largest UK base), Luton (Wizz Air, easyJet) and Gatwick (easyJet) typically have the lowest advertised ticket prices, often £30–60 one-way within Europe. But ticket price is not total journey cost.
Heathrow: £5–25 (Piccadilly Line or Elizabeth Line). Gatwick: £15–20. Stansted: £10–17. Luton: £10–15. London City: ~£3 (DLR). The cheapest transfer is London City, but it has the most expensive tickets.
Add it up: £30 ticket + £45 checked bag + £17 Stansted Express = £92. The £120 BA ticket to Heathrow often includes baggage. Plus the Elizabeth Line to central London is £12, total £132. The gap shrinks from £90 to £40. If you value your time, Heathrow may actually win.