You’ve chosen the best formula to feed your new little one and stocked up on plenty of baby bottles. Feeding your baby seems fairly simple — measure out the formula and add water, right? But — what kind of water?

Can you use tap water for formula? Does anyone even drink tap water these days? What’s the best kind of bottled water for your baby?

The good news is you can use tap water or bottled water to make your baby’s formula. But you might not be able to use the water straight out of the tap or use just any bottled water.

You actually need to become a bit of a water boiling expert and know about things you never thought of before, like how much fluoride is in your water.

Don’t worry, drinking water is safe in most of the country. And once you get the hang of mixing your baby’s formula, it’s pretty simple! You can do it in your sleep (and you’ll have to). Here’s what you need to know.

Even though we’ve been sold bottled water for a very long time, tap water in most places — not all — in the United States is safe to drink. However, it is still best to boil tap water and let it cool before you use it to make your baby’s formula.

Boiling water kills any germs, like bacteria or viruses, that might get into the water. This can happen if pipes are old or leaky, if there’s heavy rain or flooding in your area, or if there are problems with the water main or reservoir in your town.

Using a home water distillation, purification or filtering system does not remove all the germs from the water. Boiling water makes it safe for you and your baby to drink.

To boil, simply:

  1. Fill a clean pot or kettle with water.
  2. Bring the water to a rolling, bubbling boil.
  3. Let it boil for at least a full minute.
  4. Remove it from the heat.
  5. Let the water cool to about body temperature — 98.6°F (37°C).

You can also use an electric kettle to boil water. Handle boiling water very carefully. You’ll need to use both hands while near a stove or hot kettle, so don’t hold your baby while you’re making the formula; keep them safely away.

Use boiled and cooled tap water to make your baby’s formula. Test the formula’s temperature on your wrist before feeding your baby. Just sprinkle a few drops on the inside of your wrist. If it’s too hot for your wrist, it’s too hot to give to your baby!

Fluoride and tap water

Another thing to know about tap water is that in the United States most community tap water has added fluoride. This mineral is added to drinking water because it helps to prevent cavities. Fluoride is found naturally in water and soil, but the levels are too low to have any benefit.

The American Dental Association supports the addition of fluoride to water at 0.7 parts per million to protect dental health. However, too much fluoride in the body can stain teeth with white lines, known as dental fluorosis.

Using tap water helps protect your little one’s budding teeth because it has added fluoride. But, because babies are tiny, they can sometimes get too much fluoride if you use tap water all the time.

Boiling tap water doesn’t change how much fluoride is in it. Home water filters can’t remove fluoride either. If you’re worried about your baby getting too much fluoride, alternate between using tap water and low-fluoride bottled water to make your baby’s formula.

Most bottled water comes from tap sources, so they can also have added fluoride in them. Low fluoride tap water might be labeled as “demineralized,” “purified,” distilled” or “deionized.” This means that some fluoride is removed.

You can also use liquid baby formula if you are worried about too much fluoride. These ready-to-feed baby formulas have less fluoride in them than using tap or regular bottled water.

Let your pediatrician know if you are using low fluoride water to make your baby’s formula or if you are feeding them ready-made formula. There is a possibility that your baby gets very low amounts of this mineral. Your doctor might recommend fluoride supplements for your baby when they’re 6 months old.

In some parts of the United States, homes get their drinking water from wells. Many of these are private wells that aren’t checked by health inspectors. This means that sometimes they might have higher levels of minerals than are normally allowed.

Well water can also get contaminated with toxins from the dirt or water around it. In rare cases, the toxins can be so high that they can poison babies, children and even adults.

If your home gets its tap water from a well ask your local municipality to make sure it is tested regularly. If it’s a private well, you can seek testing yourself. If you’re not sure if the well water is tested or safe, avoid using it to make your baby’s formula. Use low fluoride bottled water for your baby instead.

If you prefer to use bottled water to make your baby’s formula, you might be able to find bottled water that’s sold just for babies. This means that these companies have followed guidelines to make sure the water is sterilized by boiling before being bottled.

However, these can be hard to find and are more expensive than regular bottled water. You can use any bottled water to make baby formula.

Yes, you still need to boil it. While bottled water is safe to drink for adults, it might not be as safe for babies. Plus, some bottled water may have been on the shelf for a while or gotten contaminated. It’s best to be on the safe side and take the time to boil even bottled water.

You can boil water in advance so that its ready for when your baby has the hungry cry. How you handle and store the water is just as important as getting it ready by boiling it.

  • The first step is to always wash your hands before you touch anything (including your baby).
  • Use sterile glass jars or jugs with lids to store boiled water. You can sterilize them by pouring boiling water into them and rinsing out with boiled water. Don’t use tap water to rinse them out; they won’t be sterile anymore if you do!
  • In the same way, remember to sterilize your baby’s bottles after you’ve washed and rinsed them with tap water.

You can even bank some of that safe baby formula after you’ve mixed it. A bottle of prepared formula can sit on the counter for about 2 hours. An unused bottle of mixed formula can stay fresh in the fridge for up to 24 hours. This way you aren’t stumbling around in the middle of the night mixing up your baby’s fix!

If your little one decides they’d rather sleep or play than feed in the middle of a bottle, dump the rest of the formula within an hour. Don’t refrigerate a partially used bottle or mix it with new formula. It’s no longer sterile and can go bad faster than a fresh bottle of formula.

You can use both tap water and bottled water to make your baby’s formula. In both cases, you must sterilize the water by bringing it to a boil — unless you can find bottled water that is specially made for infant formula, but that’s just getting fancy!

If you’re worried about fluoride, check with your doctor about alternating tap water and low fluoride bottled water or only using bottled water. If your home gets well water, its best to use bottled water.