Introducing formula feeds

baby having a break from feeding

If you are breastfeeding but want to introduce formula, it's best to gradually reduce the amount of breastfeeds. This will help your baby get used to the change and stop your breasts becoming sore (from being too full of milk) and leaking. Gradually cutting down on breastfeeding also reduces your risk of developing mastitis.

Introducing infant formula will probably reduce the amount of breast milk you produce. To keep your breast milk supply going, it is important to keep breastfeeding your baby regularly. If you are combining with formula milk, try to prioritise breastfeeding where possible; you could start by replacing one breastfeed a day with a bottle feed.

It helps to drop breastfeeds one at a time – whichever one meets your needs. If you replace a breastfeed with a formula feed, it can take around 5 to 7 days for your breasts to adjust to the missing feed.

Offering the first bottle

You might find that your baby refuses to take a bottle – this is especially common if your baby has been successfully breastfeeding for some time. It might be tricky at first, but if you go slowly and work at your baby's pace, they will get the hang of it!

Check out our guide to introducing a bottle for more help.

You'll find more general information on how to bottle feed and how to make up a formula feed in our bottle feeding section.

How much formula feed?

The best guide to how much formula feed to give is your baby. Responsive or "on demand" feeding will help prevent overfeeding. Your baby's needs will change over time and as they develop, so they will let you know how much they need. See our guide to feeding on demand.

You should always follow the manufacturer's instructions about how much formula to use in a bottle, but if your baby is full, throw away any leftover milk.

Generally, each breastfeed you drop will be replaced with one bottle of formula feed.

There's no fixed schedule or amount of breast to bottle feed, it's up to you and your baby.

Some people choose to replace the bedtime breastfeed with a bottle as they believe it will help their baby to sleep better. Remember very young babies need to feed little and often so this will probably not be the case for a newborn.

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