Ho Chi Minh City does not run on one payment method. It runs on two, and the trick is knowing which one a given place expects before you're standing at the counter holding the wrong thing.
The short version: bring both
Cards work at a real slice of the city's businesses, and cash is still required almost everywhere else. Hotels, larger restaurants, shopping malls, convenience store chains, and most tour operators that cater to foreign visitors will take a card without hesitation. Street food stalls, local markets, small family-run shops, motorbike taxi drivers, and many independent cafes will not. Neither system has fully replaced the other, and that split tracks fairly closely with the size and formality of the business, not with the neighborhood or how touristy it feels.
Plan to carry cash for anything under the scale of a sit-down restaurant, and expect a card to work at anything larger. That single rule covers most of what you'll run into day to day.
Where cards genuinely work
International hotel chains, serviced apartments, and mid-range to upscale hotels almost always take Visa and Mastercard, and often American Express too. Shopping malls like Vincom Center or Saigon Centre, along with the retail chains inside them, are set up for card payments the same way a mall back home would be. Larger restaurants aimed at both locals and visitors, especially anywhere with a printed menu and table service, typically have a card machine at the register.
Ride-hailing apps such as Grab let you link a card directly in the app, which sidesteps the cash-or-card question for a huge share of your daily transport. If you're booking tours, transfers, or activities through an established operator's website in advance, card payment is standard there as well.
Where cash is still the only option
Street food is the clearest case: a bowl of pho from a sidewalk vendor, a banh mi stand, or a plastic-stool beer corner has no card reader and no interest in getting one. Wet markets and most souvenir stalls operate the same way. Local, non-chain cafes and smaller restaurants without a visible payment terminal fall into this category too, and it's often not obvious from the outside which restaurants have one and which don't.
Traditional taxis you flag down on the street, rather than book through an app, may or may not have a card reader that actually works, so don't count on it. Motorbike taxi drivers booked informally, tipping, and any negotiated price for goods at a market are cash transactions by nature.
Getting dong out of an ATM
ATMs are common through District 1 and other central areas, run by both Vietnamese banks and international ones with a local presence. Using one is the most practical way to get dong, Vietnam's legal tender issued by the State Bank of Vietnam, at a fair, transparent exchange rate, since it's tied to your card network's rate rather than a currency counter's markup.
Confirm two separate fees with your own bank before you leave: the fee your bank charges for a foreign ATM withdrawal, and any fee the Vietnamese ATM itself adds on top, which is usually disclosed on screen before you confirm the transaction. These vary by bank and change over time, so a number quoted in an old blog post or forum thread isn't something to rely on. If your bank has a partner network in Vietnam, using those specific ATMs can reduce or eliminate one side of that fee.
What your card issuer actually charges
Separate from the ATM question is the foreign transaction fee your card issuer applies to purchases made in dong. Some travel-focused cards waive this fee entirely, while others add a percentage to every foreign purchase regardless of whether you withdrew cash or paid directly. This is worth checking before the trip, not after your statement arrives, since it affects whether card payments are actually cheaper than carrying cash once you account for the fee.
Contactless tap-to-pay is available at a growing number of card-accepting businesses, mirroring the same split described above: chains and larger venues are more likely to support it than independent shops.
What this guide doesn't cover
This article doesn't state specific ATM fee amounts, foreign transaction fee percentages, or current exchange rates, because all three change and vary by bank. Before you travel, check your own bank's international withdrawal fee, your card issuer's foreign transaction fee policy, and compare a couple of exchange rates once you're in the city rather than assuming the airport rate is representative. With that confirmed, the cash-and-card mix described here should match what you actually encounter on the ground.