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formula milk

Read our step-by-step guide to making up a bottle of formula.

Good hygiene is really important when preparing a bottle of formula for your baby (NHS Choices, 2016a, 2018). A baby’s immune system isn’t as well developed as an adult’s. This makes them more vulnerable to illness and infection, particularly diarrhoea and vomiting

Watch our simple step-by-step guide on how to make up a bottle of formula milk for your baby.


Follow our step-by-step guide to making up a bottle of formula.

Step 1: Fill up the kettle with fresh water

Use at least 1 litre of fresh tap water. Don’t boil and use water that has already been boiled, or use artificially-softened water. Bottled water is also not recommended for making up a feed as it’s not sterile and may contain too much salt (sodium) or sulphate (NICE, 2105; NHS Choices, 2015, 2016a, 2017, 2018).

Filling up a kettle of water

Step 2: Boil the water

Then leave it to cool for up to 30 minutes, so that it has cooled but is still at least 70°C.

Step 3: Clean area and wash your hands

It's important to disinfect the surface you are going to use and wash your hands thoroughly.

cleaning surface

Step 4: Rinse and shake excess water

If you’re using a cold-water steriliser, shake off any excess solution from the bottle and the teat, or rinse them with cooled boiled water from the kettle (not tap water). Then put your sterilised baby bottle on the cleaned, disinfected surface.

Step 5: Pour the water in

Use the amount of water you need and double check the water level is correct. Always put water in the bottle first, while it’s still hot, before adding any powdered formula.

Step 6: Loosely fill the scoop with formula powder

Do this according to the manufacturer's instructions. Level it off using either the flat edge of a clean, dry knife or the leveller provided. Different tins of formula come with different scoops. Make sure you only use the scoop that comes with the formula.

bottle of formula

Step 7: Put the teat back on the bottle

Holding the edge of the teat, put it on the bottle. Then screw the retaining ring onto the bottle. Cover the teat with the cap and shake the bottle until all of the formula powder dissolves.

Step 8: Cool the bottle for your baby

It's important to cool the formula so it's not too hot to drink. You can do this by holding the bottle (with the lid on) under cold running water.

Step 9: Test the temperature

Always test the temperature of the formula on the inside of your wrist before feeding it to your baby. It should be body temperature, which means it feels warm or cool, but not hot.

(NHS Choices, 2016a)

Step 10: Throw away un-used feed

If there is any made-up formula left after your baby has finished feeding, always throw it away.

Tips for preparing formula feeds

  • Always follow manufacturers' instructions carefully as they vary on how much water and powder to use.
  • Never add extra formula powder because this can make your baby constipated or dehydrated. Too little powder may mean your baby doesn't get the nourishment they need.
  • You shouldn't add anything else to the bottle like sugar or cereals either.
  • Never warm up formula in a microwave, as it may heat the feed unevenly and scald your baby's mouth.
  • You should make up each feed as your baby needs it because bacteria multiply very quickly at room temperature. You might be surprised that even sealed formula packets can sometimes contain bacteria.
  • Very young babies and babies with poorer immune systems, like premature babies, are more vulnerable to bacteria. It’s particularly important to follow these guidelines or consider using sterile ready-made liquid feeds if your baby was born prematurely (NHS Choices, 2015).

Further information

NCT supports all parents, however they feed their baby. If you have questions, concerns or need support, call our support line on 0300 330 0700, whether you are using formula milk, breastfeeding or mixed feeding. If you’re concerned about your baby’s health talk to your health visitor or GP.

NHS. (2015) Start4Life guide to bottle-feeding. Available from: [Accessed 21st November 2017]

NHS Choices (2016a) How to make up baby formula. Available from: [Accessed 21 November 2017]

NHS Choices (2016b) Sterilising baby bottles. Available from:  [Accessed 21st November 2017]

NHS Choices (2016c) Types of formula milk. Available from:  [Accessed 21st November 2017]

NHS Choices (2017) Formula milk: common questions. Available from: [Accessed 21st November 2017]

NHS Choices (2018) Bottle-feeding advice. Available from: [Accessed 21st November 2017]

NICE (2015) Clinical Guidance CG37. Postnatal care up to 8 weeks after birth. Available from: [Accessed 21st November 2017]

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