Every so often, a flight appears at a price that seems impossible: a business class ticket across the Atlantic for the price of a dinner, or a round trip to Asia for less than a tank of fuel. These are error fares, mistakes in an airline's pricing system, and they are real. Travellers who find them quickly can fly for a fraction of the normal cost, but booking one safely requires knowing the rules.

Error fares happen when something goes wrong in the complex chain of pricing data between airlines, booking systems and travel agencies. A currency conversion error, a missing fuel surcharge, a misplaced decimal point, or a fare filed without taxes can all produce a ticket price far below the intended amount. These mistakes are rare, but with thousands of fares published every day, they happen regularly.

Most error fares are spotted within hours by fare-tracking websites and travel communities, which share them widely. That means the window to book is short, often just a few hours before the airline notices and fixes the price. Speed matters, but so does caution, because not every error fare is honoured.

Whether an error fare is honoured depends on the airline, the law in the country of sale, and how obvious the mistake was. Some airlines honour error fares as a goodwill gesture, especially when the mistake was theirs. Others cancel the tickets and refund the purchase, arguing that the price was an obvious error no reasonable person would expect to be valid.

In some countries, consumer protection rules require airlines to honour the published price, while in others the airline has more freedom to cancel. There is no guaranteed outcome, which is why the first rule of error fares is never to book non-refundable hotels or make other firm plans until the airline confirms the ticket. Wait for the e-ticket and, ideally, a few days of silence from the airline before spending more money on the trip.

When you spot a possible error fare, act quickly but carefully. Book directly with the airline if possible, because third-party bookings add another layer of complication if the ticket is cancelled. Use a credit card, which gives you chargeback protection if things go wrong. Take screenshots of the price, the booking confirmation and the fare rules.

Do not call the airline to ask about the fare, because that can draw attention to the mistake and speed up its cancellation. Do not book connecting travel, hotels or tours until the ticket is confirmed and some time has passed. And be ready for disappointment: many error fares are cancelled, and that is part of the game. When one is honoured, though, it can be the cheapest flight you will ever take.

It is also important to know that error fares are not the only way to find unusually cheap tickets. Airlines regularly publish genuine sale fares, mistake-adjacent pricing glitches, and flash sales that are intentional but still very cheap, and these are honoured far more reliably than true errors. Following fare alert services and setting up price alerts for routes you care about can surface these deals without the risk of cancellation that comes with error fares. The skills are the same: act quickly, book with a credit card, and keep your confirmation. Over time, a traveller who watches fares patiently will find several genuinely cheap tickets a year, and those are often a better use of time than chasing the rare error fare that may not survive.

Error fares are real but unreliable. Book quickly with a credit card, keep your proof, and do not spend on hotels or other plans until the airline confirms the ticket. Most will be cancelled, but the ones that survive are unforgettable bargains.