Two travellers buy the same meal in the same restaurant on the same evening and pay different amounts for it. Not because one of them negotiated, but because of what happened after the card was tapped: which currency the bill was settled in, what their card issuer charges for a purchase in a foreign currency, and what margin sat inside the exchange rate they were given.

None of those costs appear on the menu. All of them are knowable in advance. Travel money is less about hunting for the single cheapest card in the world and more about understanding the three places a cost can hide, then building a setup where one declined card does not end your evening.

This guide covers how card pricing actually works, cash and ATMs, the currency-choice trap that costs more than most people realise, what to carry as backup, and how to keep the whole thing organised. Fees and rates change constantly, so read everything here as structure rather than numbers, and confirm current terms with your own bank and card providers before you travel.

The three places a cost hides

Every foreign purchase passes through the same three gates, and a cost can sit at any of them.

The exchange rate. If you pay in a foreign currency, someone converts it. A card that converts close to the wholesale or mid-market rate charges you near cost; a card that applies its own rate adds a margin on top. This is usually the biggest single difference between a good travel card and an ordinary one, and it is invisible on the receipt.

The transaction fee. Many cards add a percentage charge on purchases in a currency that is not your home currency. Some charge the same on cash withdrawals, often with a minimum amount. A card with no foreign transaction fee but a poor exchange rate is not automatically better than the reverse, which is why the rate and the fee have to be read together.

The cash machine’s own charge. The operator of the ATM, not your bank, sets the fee for using it, and it is usually a flat amount per withdrawal. Some machines also apply their own exchange rate on top. Withdrawing a larger amount less often reduces the impact of a flat fee, while small frequent withdrawals are the most expensive pattern available.

A fourth cost only appears when something goes wrong: the cost of having no working payment method at all. That is not really a fee, and it is the reason a backup plan belongs in this guide rather than on a packing list.

Card types and what each is actually good at

Cards differ far less by brand than by how they are priced. Four broad types cover most travellers.

• A specialist multi-currency or travel card. Built around holding and spending in several currencies, and typically designed so you can see the exchange rate and the fee separately. Strong for everyday spending and ATM withdrawals abroad. Its weakness is that it is not a credit card, so it cannot satisfy a deposit hold that specifically requires one.
• A credit card with no foreign transaction fee. Useful for purchases, hotel pre-authorisations and car hire deposits, because a credit card is often the only instrument a hold will accept. Check the exchange rate margin as well, since no fee does not promise the best rate.
• A standard credit card from your main bank. Convenient and almost universally accepted, but frequently the most expensive way to spend abroad once the transaction fee and rate margin are combined. Reasonable as a backup, questionable as your primary card.
• A debit card on your everyday account. Practical for cash, but often carries a withdrawal fee, a foreign transaction fee, or both — and is normally refused for deposit holds.

The useful mental model is to pair one card for spending with one card for guarantees. A multi-currency card handles restaurants, transport and cash; a credit card handles the hotel hold and the rental car. Compare card fees on the three features that matter to you — rate margin, foreign transaction fee and ATM charge — rather than on marketing categories.

Cash, ATMs, and how much to carry

Cash is not dead, and the right amount to carry is a judgement call rather than a rule. What matters is having enough for the situations where a card cannot help: a small taxi, a market stall, a rural bus, a tip, or a terminal that happens to be offline.

Treat cash as insurance for the first and last day of each stop rather than as your main spending method. On arrival you may need transport, a snack and a tip before you have located a working ATM. On departure you may need to settle something small in a hurry. A modest amount in local currency, in hand from the moment you land, removes most of that friction.

For ATMs, a handful of habits reduce cost consistently. Use machines attached to banks rather than standalone machines in tourist areas, where fees and rate margins both tend to be worse. Decline the machine’s offered conversion, which I will come to below. Withdraw larger amounts less often so flat fees do less damage, while balancing that against carrying too much cash. And if a machine refuses your card, do not feed the same card in repeatedly — try your other card or a different machine, because repeated attempts can look like fraud to an issuer’s monitoring system.

If you are travelling somewhere card acceptance is patchy outside the cities, plan the cash side deliberately rather than hoping. Some destinations reward more preparation than others; our Morocco guide for first-timers covers how daily money handling actually works there.

The currency-choice trap

This is the most expensive routine mistake in travel money, and it is presented to you as a helpful service.

When you pay by card abroad, the terminal may offer to charge you in your home currency instead of the local one. It sounds like certainty: you know exactly what you are paying. What it usually means is that the merchant’s bank or the terminal operator performs the conversion at its own rate, with a margin built in, and that margin often exceeds whatever your own card would have charged for the foreign currency transaction.

The rule is simple and rarely wrong: always choose the local currency. Let your own card issuer or travel card do the conversion. This applies to card terminals, to ATMs, and to online bookings with foreign merchants. If a screen shows two amounts, pick the one in the currency of the country you are standing in.

The same principle applies before you leave. Buying foreign cash at an airport desk, or exchanging at a hotel reception, usually produces the worst rate of the entire trip, because you are paying for convenience at a moment when you have no alternative. If you want cash for arrival, get a small amount from a cheaper source in advance and plan to use an ATM for the rest.

What to carry as backup, and how to organise it

A money setup fails for boring reasons: a card gets blocked by a fraud system, a wallet is lost, a phone battery dies, a banking app logs you out at the worst moment. Redundancy is the fix, and it is best arranged in layers.

1. Carry two cards from different issuers. Two cards from the same bank may share the same fraud system and the same outage, which defeats the purpose entirely.
2. Split them between two places. One on you, one in your main bag or the hotel safe. Never keep everything in a single wallet.
3. Keep some cash away from your cards. If a wallet disappears, cash in a different pocket is what gets you back to your accommodation.
4. Save your bank’s international contact number offline. You are most likely to need it when your phone has no data. Photograph the back of your cards, or note the numbers somewhere secure and available without a connection.
5. Set your issuer’s travel controls. Many banks let you declare which countries you will use, so a legitimate purchase abroad is not flagged as suspicious.
6. Carry a physical card, not just a phone wallet. Rental desks and some hotels want the physical card, and a dead battery should not leave you unable to pay.

A slim travel wallet that keeps a passport, several cards and a pen in one place makes all of this easier, and separating documents from daily spending money is more useful than it sounds. It is also worth knowing how your issuer replaces a lost card while you are abroad: replacements are not couriered everywhere, and not quickly, which is exactly why the second card matters.

Money tasks to do before you fly

Ten minutes of preparation removes most of the friction, and it is best done in one sitting.

• Confirm the foreign transaction fee and exchange rate structure on every card you plan to take.
• Check your credit card’s limit against any deposit hold you expect, and confirm the card is accepted for holds.
• Tell your issuers you are travelling, and enable whatever country controls they offer.
• Save your bank’s international contact number and your card numbers somewhere offline.
• Decide your cash plan: how much you want on arrival, and where you will withdraw the rest.
• Carry a small amount of local currency for the first day, bought from a cheaper source than an airport desk.
• Pack a note of any card benefits you may rely on, such as damage cover for a rental car.

Frequently asked questions

Should I always pay in the local currency?

When a terminal or ATM offers to charge you in your home currency, decline it and choose the local one. The conversion offered at the point of sale usually includes a margin set by the merchant’s bank or the machine operator, and that margin is often larger than the fee your own card would charge for a foreign currency transaction. If two amounts are shown, choose the local currency and let your own card do the conversion.

Are travel cards better than a normal credit card?

They solve different problems, which is why many travellers carry both. A specialist travel card usually offers a better exchange rate and lower fees for everyday spending and cash withdrawals, but it is not a credit card and cannot be used for deposit holds. A credit card is the practical instrument for hotel pre-authorisations and car hire, so keep one for those and use the travel card for spending.

How much cash should I carry?

There is no universal figure, and anyone quoting one is guessing about your trip. Carry enough in local currency to cover the first and last day of each stop — transport, a snack, a tip — plus a small reserve. Then judge the rest by how reliably cards are accepted where you are going. A card-first trip with a cash float for markets, buses and offline terminals is usually the right balance.

What should I do if my card is declined abroad?

Try a second card from a different issuer first, and use a different ATM or terminal rather than repeating the same attempt. Then contact your bank using the international number you saved offline, since a decline is often a fraud control rather than a lack of funds. This is also why a card that has never been used abroad is worth activating before your trip rather than during it.

The bottom line

Travel money comes down to reading the exchange rate and the fee as one combined cost, choosing the local currency at every terminal, and never depending on a single card. Do those three things and the amounts you pay abroad stop being a mystery. Skip them and the same holiday quietly costs more, in ways that never appear on a receipt.

Set up one card for spending and one for guarantees, keep them in different places, and carry a little local cash from the moment you land. Compare card fees before your next trip, and if you are booking anything in advance, our guide to finding cheaper flights with flexible dates and where to book hotels now both explain how the same currency and payment choices apply to bookings.