The Short Answer: No, Don't Drink the Tap Water
This is the question every traveller asks in the first hour, so let's settle it immediately: do not drink tap water anywhere in Vietnam — not in Da Nang, not in Hoi An, not in a five-star resort, not in Hanoi or Ho Chi Minh City. Locals don't drink it either.
Here's the nuance that most guides skip. The water leaving Da Nang's municipal treatment plant is actually chlorinated and treated to a reasonable standard. The problem is everything that happens after the plant: aging distribution pipes with cracks and joints that let groundwater seep in, pressure drops that pull contaminants into the lines, and — most importantly — the rooftop storage tanks that almost every building uses. Water can sit in those tanks for days in 35°C heat, and they are rarely cleaned. By the time water reaches your tap, it can carry bacteria (E. coli, Salmonella), parasites (Giardia), and viruses that your gut has never met before.
The fix is simple and cheap:
- Bottled water costs 5,000–10,000 VND (about $0.25–0.40) at any convenience store. La Vie, Aquafina, Dasani, and Vinh Hao are reliable local brands. Check the seal is intact.
- Your hotel provides for you. Nearly every hotel in Da Nang and Hoi An puts two complimentary bottles in the room daily and provides an electric kettle. Ask reception for more — it's normal.
- Large 19-litre dispenser bottles are what apartments and homestays use. The water from these dispensers is purified and fine to drink.
- Filtered water from a proper multi-stage filter (RO or UV) is safe. Many modern cafés and coworking spaces in Da Nang's An Thuong area and Hoi An's An Bang neighbourhood offer free refill stations — a good way to cut plastic waste.
- Boiling works too: a rolling boil for one minute kills bacteria, viruses, and parasites. That hotel kettle is your friend.
Ice: The One Rule That Actually Matters
Travellers fear ice more than anything, and mostly they don't need to. Vietnam has a large industrial ice industry precisely because nobody drinks tap water. Learn to recognise one shape:
The cylindrical ice with a hole through the middle is safe. This "tube ice" (da vien) is mass-produced in licensed factories from purified water, bagged, and delivered daily to cafés, restaurants, and bars. If your drink arrives with uniform cylinders that have a neat hole down the centre, that ice never touched tap water. Virtually every established café and restaurant in Da Nang and Hoi An uses it.
Be more careful with block ice. Large blocks (da cay) hand-crushed with a pick or a cloth bag are traditionally used for keeping goods cold, not for drinks. At rural roadside stalls or markets, crushed block ice may be made from untreated water or handled with bare hands on the ground. It's not automatically dangerous, but it's the riskier category. If a remote stall hand-chips ice into your sugarcane juice, that's the moment to politely ask for no ice ("khong da" — kohng dah).
In practice: in the tourist areas of Da Nang (My Khe beachfront, An Thuong, Han riverside) and Hoi An (Ancient Town, An Bang) you can order iced drinks with confidence at any café that looks like it has regular ice deliveries — which is nearly all of them.
Coffee and Tea: Enjoy Freely
Good news for anyone who came to Vietnam partly for the coffee. Hot coffee and hot tea are safe everywhere, from fancy roasteries to a plastic-stool street vendor. The water is boiled, and boiling kills every pathogen you're worried about. The free green tea (tra da) poured at restaurants is brewed from boiled water; if it's iced, the same tube-ice rule applies.
Ca phe sua da — iced coffee with condensed milk, the drink of the country — is fine at any proper café: boiling water through the phin filter, condensed milk from a sealed can, industrial tube ice. The combination that has launched a million happy afternoons is not the thing that will make you sick in Vietnam. Street food hygiene is a far bigger factor — see our food poisoning guide for that side of the story.
Brushing Your Teeth
This one divides travellers, so here's the honest medical view. For most healthy adults, brushing with tap water is fine. The exposure is tiny — you wet the brush, you spit, you rinse briefly. The infectious dose for most waterborne pathogens is higher than what you swallow while brushing, which is why the majority of travellers who brush from the tap never notice a thing.
Use bottled water for brushing if any of these apply:
- You have a sensitive stomach or a history of travellers' diarrhea on previous trips
- You're immunocompromised, pregnant, or taking acid-suppressing medication (PPIs reduce your stomach's acid barrier against bacteria)
- You're already unwell and your gut is fighting something
- It's for a child — kids swallow more than they admit
Either way: keep your mouth closed in the shower, and don't rinse contact lenses in tap water — use proper lens solution only.
Babies and Formula: The Strict Rules
Everything above is about educated risk for adults. For infants, there is no grey area. An adult gut shrugs off a bacterial dose that can put a baby in hospital with dehydration within hours.
- Bottled water only for mixing formula — and boil it first, then cool it to the correct temperature. Boiling matters because formula powder itself is not sterile.
- Sterilize bottles and teats with boiling water from the kettle, or bring sterilizing tablets.
- Bottled water is also the rule for a baby's drinking water and for rinsing anything that goes in their mouth.
- Prefer low-mineral still water for formula (most Vietnamese purified brands like La Vie are fine; avoid mineral-heavy sparkling water).
If a baby or toddler in your family does develop vomiting or diarrhea in Da Nang or Hoi An, treat it seriously early: small frequent sips of oral rehydration solution (Oresol, sold at every pharmacy), and a doctor's assessment the same day rather than waiting it out. Our doctors do home and hotel visits for children — no feverish toddler in a waiting room.
Washing Fruit, Salads and Water Bottles
The mango you bought at Han Market or Hoi An Central Market was likely rinsed in tap water, and that's usually harmless because you peel it. The rule of thumb travellers have used for decades still works: boil it, cook it, peel it, or leave it.
- Fruit you peel (mango, banana, rambutan, mangosteen, dragon fruit) — safe. Peel it yourself with clean hands.
- Fruit you eat whole (grapes, strawberries, guava with skin) — wash with bottled or filtered water, or skip.
- Salads and raw herbs — the classic Vietnamese herb plate is washed in tap water. At established restaurants it's usually rinsed in filtered water and risk is low; at rural stalls, cooked dishes are the safer choice for a delicate stomach.
- Refilling your own bottle — only from purified dispensers or filter stations, never the bathroom tap.
"I Already Drank Some — Now What?"
You took a big gulp in the shower, or you've been filling your glass from the bathroom tap for two days before reading this. First: don't panic. A single accidental exposure very often causes nothing at all — the dose was small, the water may have been reasonably clean that day, and your stomach acid killed most of what arrived.
What to actually do:
- Stop the exposure — switch to bottled water now.
- Watch and wait for 1 to 3 days. That's the typical incubation window for the common culprits. Symptoms to watch for: loose stools, cramps, nausea, low-grade fever, unusual fatigue.
- If symptoms start, begin oral rehydration early (Oresol from any pharmacy, one sachet per 200ml of bottled water) and follow a proper plan — our travellers' diarrhea guide walks through the full protocol: what to drink, what to eat, which medicines help, and which make things worse.
- See a doctor if you have a fever above 38.5°C, blood or mucus in the stool, more than six loose stools in 24 hours, or symptoms beyond three days. These patterns can mean a bacterial or parasitic infection that needs targeted treatment, not just waiting.
If you'd rather not navigate a Vietnamese hospital with a bad stomach, that's exactly what we exist for. A licensed, English-speaking doctor from Viet Home Doctor comes to your hotel, villa, or apartment anywhere in Da Nang or Hoi An — typically within 1 to 3 hours — with rehydration supplies, testing, and medication, plus an IV drip when dehydration has gone too far for drinking to fix. We provide English medical reports for your travel insurance. Book a visit here, or browse the rest of our health guides for travellers in Vietnam.