Currency Exchange Mistakes Travellers Make — Airports, Hotels, "No Commission" Signs, Torn Notes, and Where the Good Rates Actually Are
Most of the cost of changing money comes from a handful of avoidable choices. The places that quietly charge the most, how to read a rate board, why the condition of your notes matters in Asia, and a simple rule for how much to change.
Changing cash is the oldest way to get local money and still the cheapest in a few countries, Thailand among them, if you do it in the right place. It is also where travellers lose the most through small decisions made when tired: the airport counter at arrival, the hotel desk at midnight, the booth with the friendly sign. None of these are scams; they are simply expensive.
The mistakes, ranked by cost
| Mistake | Why it costs | What to do instead |
|---|---|---|
| Changing at the airport arrivals hall | Captive customers, worst rates in the country | Change a small amount for the taxi, or none if you can pay by card or app, and change the rest in the city |
| Using the hotel desk | Convenience priced like the airport | Walk to a licensed exchange booth; in tourist areas there is one on every street |
| Trusting a "no commission" sign | The margin is in the rate, not in a fee line | Compare the buy rate for your currency between two booths; the sign is irrelevant |
| Bringing small or damaged notes | Booths in Asia pay less for small denominations and refuse torn, marked or old-series notes | Bring clean, large-denomination notes of a major currency |
| Changing everything at once | If you leave early or the rate moves, you change it back at a loss | Change what you need for a week or so; booths are everywhere |
| Accepting conversion on a card or ATM instead | Dynamic currency conversion at a worse rate than the booth | Pay in local currency; see how to avoid dynamic currency conversion |
How to read a rate board
Every board shows two rates per currency: the rate at which the booth buys your currency from you, and the rate at which it sells. You care about the buy rate for the currency you are holding. The gap between buy and sell is the booth's margin; a narrow gap means a competitive booth. Rates for the same currency vary between booths on the same street, so compare two before choosing, and expect the best rates in city centres rather than at tourist sites.
Cash versus card versus ATM
In Thailand, licensed exchange booths in Bangkok and the main tourist cities often beat the total cost of an ATM withdrawal on a foreign card once fees are counted, provided you bring clean, large notes. For card purchases a no-foreign-fee card is close to free. For cash in smaller towns, an ATM may be the only option; the fee structure is explained in ATM fees on foreign cards in Thailand, and the wider comparison in exchanging money in Thailand.
Common mistakes
- Leaving the counting to the booth. Count the notes in front of the teller before walking away; mistakes are rarely in your favour.
- Changing to a third currency. Changing dollars to baht to dong loses a margin twice.
- Changing back at the airport on departure. The same worst rate applies; spend the leftover or keep it for the next trip.
Summary
Change money in the city at a licensed booth, compare the buy rate between two of them, bring clean large notes, change a week's worth at a time, and never accept conversion to your home currency on a card or ATM. The airport and the hotel are for emergencies only.