Why do flight prices differ by country?

What point of sale means for an air fare

Airlines do not publish one price per seat. They file many fares for each route, each with its own rules, and a large part of those rules is about where the fare may be sold. In the industry's fare-rule system this is Category 15, sales restrictions: it can limit the countries and currencies of sale and name the locations where a ticket may or may not be sold, as well as the first and last dates on which it may be ticketed.

So when a fare exists only for buyers in one market, it is not hidden — it is simply not for sale anywhere else. A traveller in Germany and a traveller in Brazil looking at the same Frankfurt–São Paulo flight can be offered different fare sets because different fares are valid for sale in each point of sale.

Online, the seller has to decide which market a visitor belongs to. Typical signals are the country edition of the site, the billing country and the location of the request. That is why a price collector has to fix the market deliberately rather than inherit it from wherever the collection server happens to run.

Currency is not point of sale

The most common mistake in cross-country fare comparison is to treat the currency selector as a market selector. On most booking sites it is a display conversion: the fare you were already eligible for, multiplied by an exchange rate.

If you are building a dataset, record all four fields for every observation. A price without its market and currency is not comparable to anything.

Taxes and charges follow the departure airport

A large share of a ticket's total is not the airline's fare at all. Many governments levy a per-passenger tax on departures. The UK's Air Passenger Duty, for example, is charged on flights starting from UK airports, with three rates per destination band depending on class of travel and seat pitch.

This is why the same itinerary can look cheaper when bought in one country even though the base fare is identical: the trip has a different origin, or a different routing, and therefore a different tax stack. Researchers who measured airline prices across locations in 2014 found that some of the differences anecdotally blamed on price discrimination were explained by taxation on tickets of a particular regional origin.

Within the EU, Article 23(1) of Regulation 1008/2008 requires the final price to be shown at all times and taxes, airport charges and other charges to be itemised. That itemisation is what lets you separate fare from tax when you collect.

Fares are managed per market, not per flight

Revenue management works market by market. An airline sets fares for the origin-and-destination pair, decides how many seats to release at each price, and adjusts those decisions as bookings arrive. IATA describes the inputs to dynamic pricing as contextual: length of stay, time before travel, day of departure and arrival, competition and remaining capacity to sell.

Traditional pricing works through a maximum of 26 booking classes, one per letter. Newer continuous pricing lets an airline quote price points between those classes and adjust them in real time without filing a fare with a third-party system — which means the gap between two markets can move during the day. For how often that happens, see how often flight prices change.

What EU law says about pricing by residence

For air services from an airport in an EU Member State, Article 23(2) of Regulation 1008/2008 requires that access to fares offered to the general public be granted without discrimination based on the customer's nationality or place of residence, or on where the seller is established within the EU.

The EU's 2018 Geo-blocking Regulation does not cover this ground: it excludes transport services, and its recitals point to Regulation 1008/2008 as already containing broad prohibitions of discrimination for passenger tickets.

Outside that scope — flights departing non-EU airports, or markets outside the EU — point-of-sale fares are a normal commercial practice. This is a description of the rules, not legal advice; check with counsel before relying on it for a specific case.

How to compare fares across countries without fooling yourself

• Fix the market explicitly. Query each point of sale from inside that market — the site's country edition plus a request that originates in the country. Residential proxies with country targeting are the usual way to do that from one machine.
• Synchronise the observations. Run all markets for one route and date within the same few minutes. Availability moves; a comparison spread across hours compares two different moments.
• Split fare, tax and fees. Store the base fare, each tax line, any booking fee and the currency separately so you can tell a market effect from a tax effect.
• Keep the fare's identity. Where the page shows it, record the fare class or brand; a cheaper price in another market is often a different fare, not the same fare discounted.
• Repeat before you conclude. One gap is an anecdote. The same gap on the same route across days is a pattern.

The collection side of this — route matrices, sessions per search flow and cost per market — is covered on the airline fares page.