Banking
Handling money on the Camino is easier than ever. Most US cards work fine in Spain, and tap-to-pay with a card or your phone is accepted in most bars, shops and restaurants. But small villages and plenty of albergues are still cash only, so always carry some euros.
Before you leave:
Tell your bank and card company you're traveling, or set a travel notice in the app.
Get a card with no foreign transaction fees. Those 3% fees add up over a month.
Install your bank's app so you can check balances, move money, and lock a lost card from the trail.
Cash and ATMs
ATMs (cajeros) are easy to find in towns and cities, but not in every village. Plan ahead before long empty stretches.
Pull out a decent amount at a time. ATM fees hit every withdrawal, so a couple of trips a week beats one every day.
Use ATMs run by real banks. Avoid the stand-alone ones that charge big fees.
When the screen asks whether to charge you in dollars or euros, always choose euros. The "convenient" dollar option comes with a lousy exchange rate. Same goes for card machines in shops.
Don't bother bringing a stack of dollars to exchange. Exchange counters are hard to find along the Camino, and airport rates are bad. Just use the ATM.
Carry a backup card
You'll be on the road for weeks. Cards get lost, stolen, or eaten by ATMs. Bring at least two cards, ideally from different banks, and keep them in different places: one in your pocket, one in a money belt or hidden pouch. Don't show other people where you keep the spare.
Ask your bank about a second card on the same account. If you lose one, you can lock it in the app and keep using the other. That turns what used to be a nightmare of phone calls into a minor annoyance.