Baby Formula and Bottled Water During a Boil Water Advisory

A boil water advisory is inconvenient for adults. For a newborn, it is a genuine safety issue, because infants drink only water-based liquids, have an immature immune system, and can dehydrate within hours.

The good news is that the guidance is clear and the safest option requires no water at all. The CDC’s order of preference is straightforward: breast milk first, ready-to-use formula second, powdered formula mixed with safe water last.

This guide covers how to prepare each type during an advisory, the correct water temperature for powdered formula, how to sanitize bottles, and what to do if the power is out and you cannot boil anything.

The short answer

1. Ready-to-feed (ready-to-use) formula is the safest choice. It needs no water and no mixing. If you can buy it, do.
2. Powdered formula must be mixed with bottled water, or with tap water boiled for one minute and cooled.
3. For babies under 2 months, premature babies, or babies with a weakened immune system, the CDC advises mixing powder with water that has been boiled and then left to cool for about five minutes — roughly 158 °F (70 °C) — to kill *Cronobacter*, then cooling the bottle before feeding.
4. Never mix formula with unboiled tap water during an advisory, and never use water from a filter pitcher as a substitute for boiling.
5. Sanitize every bottle, nipple and ring before use.

Why formula is a special case

Powdered infant formula is not sterile. It can contain *Cronobacter sakazakii*, a bacterium that causes rare but severe infections — meningitis, sepsis, necrotizing enterocolitis — in newborns. The risk is small per bottle, but it is highest in the first two months of life.

Adding contaminated tap water to that powder does two things: it introduces new pathogens, and it creates a warm, nutrient-rich liquid that lets them multiply during the time between mixing and feeding.

That is why the guidance is not simply “use bottled water.” For the youngest babies, the water itself must be hot enough to kill what is in the powder.

Step by step: powdered formula during an advisory

1. Wash your hands with safe water and soap, then dry them on a clean towel.
2. Boil the water. Fill a kettle or pot with tap water, bring it to a rolling boil for one minute, then turn off the heat.
3. Decide the temperature.

• For a healthy baby over 2 months: let the water cool to room temperature.
• For a newborn under 2 months, a premature baby, or an immunocompromised baby: let it cool for about five minutes, to roughly 158 °F (70 °C), then mix.

1. Measure the water into the bottle first, then add the powder. Use the scoop that came with the formula, loosely filled and leveled — not packed.
2. Cap and swirl gently to mix. Do not shake hard; it creates foam and air bubbles.
3. Cool the bottle under running water or in a bowl of cold water until it is lukewarm. Test a drop on the inside of your wrist.
4. Feed within two hours. Discard anything left in the bottle after the feed.

If you are using a pitcher method for the day, mix with safe water, store covered in the fridge, and use within 24 hours.

Ready-to-feed and liquid concentrate

Ready-to-feed is the simplest option: open, pour, feed. No water, no mixing, no temperature question. It costs more, which is why many families use it only during advisories.

Liquid concentrate must be diluted, usually one part concentrate to one part water. Use bottled or boiled-and-cooled water, follow the label ratio exactly, and never dilute more than instructed — over-dilution causes dangerous electrolyte imbalances in infants.

Sanitizing bottles and nipples

The CDC’s advisory guidance is explicit: sanitize all baby bottles. During an advisory, that means:

1. Wash bottles, nipples, rings and caps in hot soapy water made from safe water.
2. Rinse with safe water — not tap water.
3. Boil them fully submerged for five minutes, or use a steam sterilizer or microwave steam bag with safe water.
4. Air dry on a clean rack, covered with a clean cloth.

If you have a dishwasher with a sanitizing cycle that reaches 150 °F (66 °C) in the final rinse, it can replace the boil step — but only if your machine has that cycle and the manual confirms the temperature.

Breastfeeding and pump parts

Breast milk remains the best option and needs no water. If you pump:

• Wash pump parts with hot soapy water made from safe water, then rinse with safe water.
• Sanitize once a day by boiling for five minutes, or use a steam bag.
• Wipe the pump motor with a disinfectant wipe; do not immerse it.
• Store expressed milk according to the usual rules — room temperature for up to four hours, fridge for up to four days, freezer for six months.

If you are supplementing, use ready-to-feed for the supplement rather than powder during the advisory.

Storing and warming

• Prepare only what you need for the next 24 hours.
• Store mixed formula in the fridge at 40 °F (4 °C) or below, covered.
• Warm by placing the bottle in a bowl of warm water, not in the microwave — microwaves heat unevenly and can scald a baby’s mouth.
• Never refreeze or reheat a bottle that has already been fed from.

If the notice is about chemicals, not germs

Boiling does not remove lead, nitrate, fuel or pesticides — it concentrates them. The CDC is direct about this: water contaminated with harmful chemicals cannot be made safe by boiling, disinfecting or filtering.

In a “do not drink” or “do not use” situation:

• Use ready-to-feed formula only, or mix powder with commercially bottled water.
• Do not use tap water for bathing a baby either; sponge-bathe with bottled water.
• Follow your health department’s instructions for when the water is safe again.

Our explainer on what boiling does not remove covers the chemistry, and boil water advisory vs. order explains how to read the notice you received.

What if you cannot boil water?

Power outages often accompany the events that cause advisories. If you cannot boil:

1. Buy ready-to-feed formula if any store nearby is open.
2. Use commercially bottled water to mix powder. This is not sterile, but it is far safer than tap water during an advisory.
3. Use a cordless kettle, a camp stove or a microwave if you have one and can operate it safely outdoors or in a ventilated space.
4. Ask for help. WIC offices, pediatricians, hospitals and local emergency services can advise on supplies during a prolonged advisory.

Do not use water from a swimming pool, a hot tub, a garden hose or a well that has been flooded.

Frequently asked questions

Can I use bottled water to mix formula without boiling it? Yes. Commercially bottled water is acceptable for mixing. For newborns and immunocompromised babies, the hot-water method is still preferred when using powder.

Is distilled water better than spring water for formula? Distilled is fine, but it lacks minerals; spring water is also fine. Avoid mineral water with high sodium content, and never use flavored or carbonated water.

Do I need to boil water for a baby over 6 months? The advisory applies to everyone. Boil or use bottled water for all formula and drinking water, regardless of age.

Can I rinse the bottle with tap water after sterilizing? No. Rinse with safe water, or skip rinsing and let it air dry.

What if my baby already drank formula mixed with tap water? Most babies will be fine. Watch for vomiting, diarrhea, poor feeding or fever, and call your pediatrician if anything seems off — especially in the first two months.

Bottom line

During a boil water advisory, ready-to-feed formula is the simplest and safest choice. If you use powder, mix it with bottled water or boiled-and-cooled tap water, and for newborns use water at about 158 °F (70 °C) to kill *Cronobacter*. Sanitize bottles, never rinse with tap water, and switch to bottled or ready-to-feed entirely if the notice concerns chemicals rather than germs.

For the household routine, see what to do during a boil water advisory and brushing teeth and making ice. For current notices, check the live notices page.

Sources

• CDC, *Infant Formula Preparation and Storage*: https://www.cdc.gov/infant-toddler-nutrition/formula-feeding/preparation-and-storage.html
• CDC, *Drinking Water Advisories: An Overview*: https://www.cdc.gov/water-emergency/about/drinking-water-advisories-an-overview.html
• CDC, *How to Make Water Safe in an Emergency*: https://www.cdc.gov/water-emergency/about/index.html
• FDA, *Infant Formula* — safety and preparation: https://www.fda.gov/food/people-risk-foodborne-illness/infant-formula