Bottle Feeding 101: How to Clean and Sterilise Baby Bottles

The World Health Organization (WHO) recommends that babies are exclusively breastfed for the first six months of life and continue to be breastfed alongside complementary foods for up to two years of age and beyond. When a baby does not receive breast milk, a scientifically developed infant formula is the only suitable and safe alternative.
Māmā feeding baby with a bottle
PHOTOGRAPHY Catherine Smith @catherinesmithphotography
MĀMĀ Lauren
PĒPI Sophie

A step-by-step guide for how to clean and sterilise feeding equipment for your pēpi.



You need to clean your baby’s bottles after every feed, including the teats, caps and rings, making sure there is no milk left in them. If you can, try to clean the equipment straight after the feed. Then you can store the clean feeding equipment ready for sterilising.


  1. Thoroughly wash your hands with hot water and soap and dry them well with a clean cloth or paper towel.
  2. Fill your sink with hot soapy water.
  3. Clean the bottles inside and out, using a bottle brush.
  4. To clear the hole in the teat, squirt some water through it.
  5. Clean the teats inside and out, using a teat brush.
    Note: If you notice any cracks in the teat, throw it away. Damaged teats can grow bacteria which can make your baby unwell.
  6. Thoroughly clean any other equipment in the hot soapy water, such as bottle rings and caps.
  7. Rinse all the equipment well in clean, cold running water before leaving them to air dry.

You can use a dishwasher to clean your baby’s bottle equipment but it will not sterilise it.


After you’ve cleaned your baby’s bottle-feeding equipment, it’s time to sterilise it all. This can be done by boiling, steaming or with chemicals. You can use these sterilising methods for breast pump equipment and dummies as well.



Boiling is the most reliable and cost-effective method for sterilising. All you need is a large pot with a lid and water – it’s that easy!

  1. Fill your large pot with water.
  2. Place all your equipment in the pot, ensuring everything is covered. There shouldn’t be any air trapped inside the bottles, teats, rings or caps.
  3. Put the lid on the pot and bring the water to a rolling boil. Let it continue boiling for five minutes.
  4. Turn the stove off and leave everything to cool in the pot, keeping the lid on.



If using an electric or microwave steam steriliser or chemicals to sterilise your feeding equipment, always follow the manufacture’s instructions. Leave the equipment in the steriliser until you’re ready to use it.



After sterilising, it’s best to only remove the equipment when you’re ready to use it. When removing the sterilised feeding equipment, ensure your hands are washed or use sterilised tongs. Try not to touch the inside of the bottle and the inside or outside of the teat.

If you need to store the sterilised equipment away, put the bottles together with the teat and cap and place them in a clean, sealed container in the fridge.


For further advice and information on safe formula feeding, read this booklet from the Ministry of Health.