Expressing - the basics

Expressing breastmilk is something many mums consider, whether it’s for returning to work, building up a supply, or simply having milk ready when needed.

There’s no single right way to approach it—what matters most is finding what works for you and your baby.

You can express milk by hand, with a manual pump, or with an electric pump. Your choice may depend on your situation and how much milk you need:

• Electric breast pumps are often helpful if you’re expressing for a premature baby, planning to return to work, or trying to increase your milk supply. These situations usually need frequent expressing to collect larger amounts of milk.
• Manual pumps or hand expressing can be enough if you only need small amounts or want to have milk available for occasional feeds.

If you’re expressing for all your baby’s feeds, you’ll need to pump more than if you’re just covering the occasional feed. Research shows that breastfed babies aged 1 to 6 months take an average of 750 mL per day, but some need less and some more.^1,2

To estimate how much to express:

• Divide 750 mL by the number of feeds your baby usually has in 24 hours to get the volume for one feed.
• Multiply this by the number of feeds you’ll be away for.

Example:

If your baby has 10 feeds in 24 hours, 750 mL ÷ 10 = 75 mL per feed. 

If you’ll miss 3 feeds, aim to leave 3 lots x 75 mL which is 225 mL.

How often you need to express depends on your situation:

• If you’re exclusively expressing, aim for at least 8 times in 24 hours.
• Many mums find a routine of expressing every 2 to 3 hours during the day, with a session before bed, works well.
• Try to avoid long gaps (over 6 hours) between sessions if you’re building up supply³—this may mean expressing once or twice at night.
• Every mum is different, so you may need to experiment to find a pattern that suits you.

• The time it takes to express varies. It depends on the time of day, your technique, the type of pump and setting, and your milk flow.
• Most pumping sessions last about 15 to 20 minutes, or until milk slows to a drip. Some mums need a little more time, some less. How often you express is usually more important than how long each session takes.
• It can take a minute or two for milk to start flowing. Seeing, touching, or hearing your baby can help trigger your let-down reflex. Read more about helping your milk flow while expressing.
• Try to keep going for a few minutes after milk stops flowing, as this might trigger another let-down.
• For most mums, pumping for more than 30 minutes is too long.

• Some mums can express a lot quickly, while others find it easier to express small amounts more often (e.g., up to 30 mL every 1 to 2 hours).
• Don’t judge your milk supply by how much you can express. Pumping and hand expressing are skills that can take time to learn. Babies are usually better at getting milk than pumps.

Here are some things to consider:

• Expressing isn’t always needed. Many mums never need to express and find breastfeeding fits their lives.
• It takes time and energy. Using a pump means extra time for setup and cleaning, along with the time taken to feed the expressed milk to your baby.
• It can increase supply unnecessarily. Expressing more than your baby needs can lead to oversupply and breast inflammation.
• It takes practice. Some mums find expressing difficult, even with a good supply.
• It may not fix breastfeeding problems. If breastfeeding isn’t going well, getting support may be a better long-term fix.

Whether you’re expressing or not, you can always talk to an ABA breastfeeding counsellor for support and to make a plan that works for you.

© Australian Breastfeeding Association November 2025