Airport exchange desks price convenience twice

A rate board at an airport looks like a quoted market price. It is a retail price built from a wholesale rate, a wide margin, and the cost of trading in a terminal.

The spread is the product

Every exchange desk quotes two numbers: what it will pay for a currency and what it will charge. The gap between them is the spread, and it is where the business earns.

An interbank rate sits somewhere in the middle of that gap. The further the two quoted numbers sit from it, the more the transaction costs regardless of any stated commission.

Because both numbers are displayed, the spread is visible to anyone who looks at the buy and sell columns together rather than at the one that applies to them.

Commission is a second charge, not the whole cost

A desk advertising no commission has not removed its margin. It has moved the entire charge into the spread, where it is harder to compare against a competitor.

Conversely a narrow spread with a fixed fee can be cheaper for a large amount and much worse for a small one. The two structures cross over at a certain transaction size.

Location is a cost that gets passed on

Retail space inside a terminal is among the most expensive commercial rent available, and it is often let on a share of turnover rather than a flat sum.

The desk also holds physical stock of many currencies, which is capital sitting idle and exposed to movement. Both costs are recovered from the customers who use it.

Airside desks are typically worse than landside ones for the same reason a bottle of water is: the customer has already passed the last point where they could leave.

Ordering ahead changes the price band

Pre-ordering currency online for collection usually accesses a different, tighter rate, because the operator knows the volume in advance and does not have to hold speculative stock.

The same logic applies in reverse to leftover notes. Selling currency back at an airport desk means crossing the spread a second time on money that was already converted once.

Where cash still earns its place

Withdrawing local currency from a bank machine on arrival usually beats a terminal desk, provided the card issuer's own charges are understood beforehand rather than discovered afterwards.

A small amount of local cash carried in advance covers the first hour, when a transfer or a locker may not accept a card. Beyond that, exchanging in bulk at an airport rarely pays.