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How to prepare equipment for bottle feeding

If you are planning to bottle feed with expressed milk or baby formula, these tips will help keep your baby safe and healthy.

Formula milk must be prepared correctly and all equipment must be sterilised. Incorrect preparation or bad hygiene could make your baby seriously ill.


You must sterilise all bottles until your baby is at least 1 year old. If you use a bottle that is not sterilised you can make your baby sick.

How to sterilise equipment

Clean and sterilise all equipment before using it.

Follow these steps:

  1. Wash your hands.
  2. Wash the bottles, teats, discs, lids and tongs in warm soapy water.
  3. Sterilise the bottles, teats, discs, lids and tongs, following the manufacturer’s instructions. You can use a chemical steriliser, a steam kit or boiling water to sterilise equipment. A steam steriliser is the best. You can also get plug-in or microwaveable sterilisers.
  4. Wash and dry your hands before removing the bottles from the steriliser with the tongs.
  5. Do not rinse out the bottles after they are sterilised.

When they are put together correctly, sterile bottles with tight-fitting caps or sealing discs will be sterile for 24 hours. But this is only if you keep them closed.


Dishwashers do not sterilise bottles or feeding equipment.

After you've finished sterilising

  • It's best to leave bottles and teats in the steriliser or saucepan until you need them.
  • If you do take them out, put the teats and lids on the bottles straight away.
  • Wash and dry your hands before handling sterilised equipment. Better still, use some sterile tongs.
  • Put the bottles together on a clean, disinfected surface or the upturned lid of the steriliser.

Using a bottle to give expressed milk

Page last reviewed: 14 September 2022
Next review due: 14 September 2025