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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.

To sterilise equipment, steam is the best. Plug in and microwavable options are available.

You can also use:

  • boiling water
  • a chemical steriliser

Do not use UV sterilisers. UV sterilisers use ultraviolet-C (UVC) radiation technology. There is not enough research to show that these machines are safe and effective.

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.
  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.

Before handling sterilised equipment:

  • wash and dry your hands
  • use some sterile tongs - this is better

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: 10 January 2024
Next review due: 10 January 2027