• Skip to content
  • Skip to navigation
Raising Children Network
  • Pregnancy
  • Newborns
  • Babies
  • Toddlers
  • Preschoolers
  • School age
  • Pre-teens
  • Teens
  • Grown-ups
  • Autism
  • Disability

Preparing water for baby formula

When you’re preparing baby formula, the first step is to always wash your hands with soap. It’s also important to make sure you use a clean area to prepare the formula.

Next, boil fresh tap water in an electric kettle or on the stove top. In places with a clean water supply that meets Australian standards, hot water urns like hydroboils are also safe to use for preparing formula.

Let the water cool down to a safe temperature – lukewarm or around room temperature. This will take about 30 minutes.

You can put cooled, boiled water in sterilised bottles and store them sealed with a ring and cap in the fridge until needed. You should use these bottles within 24 hours.

It’s recommended that you sterilise bottle-feeding equipment until your baby is 12 months old. Your baby’s immune system isn’t strong enough to fight off some infections so sterilising equipment reduces baby’s chances of getting sick.

Making up powdered baby formula

Before making up baby formula, make sure to check the expiry date on the formula tin. Throw away any opened tins of formula after one month.

Here are the basic steps for adding powder to water to make formula:

  1. Read the instructions on the formula tin. These instructions will tell you how much water and powder to use.
  2. Pour the right amount of cooled, boiled water into the sterilised bottle.
  3. Using the scoop from the formula tin, measure the right number of scoops into the bottle. Level off each scoop. You can do this with a sterilised knife or something similar.
  4. Seal the bottle with a ring and cap. Tap the bottle gently on the bench so the powder falls into the water. Swirl the bottle gently, then vigorously shake the bottle. This thoroughly mixes the powder and water.
  5. Take the cap off and replace with a teat.
  6. Before feeding your baby, test the temperature of the formula by placing a few drops on the inside of your wrist. Make sure the formula isn’t too hot – it should feel just warm.

If your baby doesn’t finish all the formula, throw it away within one hour. Storing half-empty bottles of formula for future use is risky because they get contaminated with germs once they’ve been sucked on.

Never add extra formula powder to a bottle. Infant formula should always be the same strength.

Preparing infant formula in advance

It’s best to:

  • prepare only one bottle of formula at a time
  • prepare each bottle right before you feed your baby.

If you need to prepare infant formula in advance, refrigerate the formula below 5˚C within 1 hour of making it, and use within 24 hours. Store it in the back of the fridge where it’s coldest, not in the door where it’s warmer.

If you can’t keep the formula cold, throw it away after one hour at room temperature.

You can also use ‘ready to drink’ formula if preparing formula in advance isn’t an option for you or if you’re travelling.

Using formula when you’re out and about

The safest way to transport formula is to take cooled, boiled water and the powdered formula in separate containers.

But if you need to transport bottles of formula already mixed with water, make sure the formula is icy cold when you leave the house. Carry it in a thermal baby bottle pack or a cool bag with ice packs.

You can put the bottle of formula back in the fridge if it has been in the bottle pack or cool bag for less than two hours. But make sure to use it within 24 hours of when it was first prepared.

Throw away any prepared formula you haven’t used or put it back in the fridge within two hours.

Warming and cooling infant formula

There’s no need to warm formula that has been chilled or ‘ready to drink’ formula. If your baby doesn’t mind cold formula, it’s fine for your baby to have it cold.

But many babies do like their formula lukewarm or warmed a little. The safest way to warm formula is to stand the bottle in a jug of warm water.

Bottle warmers are convenient and safe as long as they have a thermostat control. Don’t leave the bottle in the warmer for more than 10 minutes. This might cause bacteria to breed in the formula or breastmilk. These bacteria are a common cause of diarrhoea.

Gently swirl the bottle or container to mix the formula after warming. Test the temperature of the formula by putting a few drops onto your wrist. It’s recommended that you don’t use a microwave to heat infant formula because it can heat the formula unevenly and the formula can burn your baby’s mouth.

If you accidentally make the formula too hot, cool it down by holding it under cold running water or placing it in a jug of cold water. Swirl the bottle and recheck the temperature on your wrist before feeding. Don’t put this bottle back in the fridge for later use.

Read more about how to bottle-feed and download our illustrated guide to formula preparation.

Supported By

  • Department of Social Services

Raising Children Network is supported by the Australian Government. Member organisations are the Parenting Research Centre and the Murdoch Childrens Research Institute with The Royal Children’s Hospital Centre for Community Child Health.

Member Organisations

  • Parenting Research Centre
  • The Royal Children's Hospital Melbourne
  • Murdoch Children's Research Institute

Follow us on social media

  • Facebook
  • Instagram
  • YouTube
  • Twitter
Join 60,000 subscribers who receive free parenting news. Sign up now
Aboriginal flag (c) WAM Clothing
Torres Strait Islands flag
At raisingchildren.net.au we acknowledge the traditional custodians of the land on which we live, gather and work. We recognise their continuing connection to land, water and community. We pay respect to Elders past, present and emerging.
  • Privacy statement
  • Terms of use

© 2006-2022 Raising Children Network (Australia) Limited. All rights reserved.

Warning: This website and the information it contains is not intended as a substitute for professional consultation with a qualified practitioner.

This website is certified by Health On the Net Foundation (HON) and complies with the HONcode standard for trustworthy health information.