Infant formula

How to get started with formula feeding your baby

Key points about infant formula

  • Infant formula will meet all your baby's nutritional needs until they are around 6 months old.
  • At around 6 months your baby will probably start eating some solid foods but will continue to need formula until 12 months of age.
  • Formula feeding your baby requires planning and organisation to make sure you have what you need when you need it.
  • This page has information about getting started with formula feeding.
Parents hug and smile with baby

There are a range of commercial infant formulas available in New Zealand. These have been developed to contain similar nutrition to breastmilk. All formulas sold in New Zealand conform to the Australia New Zealand Food Standard Code (Standard 2.9.1 – Infant Formula Products). There is no evidence that one brand is better than another.
Cows’ milk formula is usually recommended for healthy babies who are not breastfed. Use an infant formula that’s right for your baby’s age. Your baby could become ill if you feed them a formula intended for older babies. Infant soy formula and other specialised formulas are only suitable for babies with a medical reason to use them, such as having an allergy to cow’s milk. This formula must not be confused with regular soy milk, which does not provide suitable nutrition for babies.

Infant formula is not sterile. It is important to check the expiry date on the formula tin to ensure that the product has not expired. The expiry date applies until the seal is broken. Once the seal of the formula tin is broken, it should be used within 4 weeks.

(KidsHealth, NZ, 2017)

The amount of formula will vary depending on your baby's age, how much they weigh, the time of day, their activity level and their rate of growth. The formula tin will list general guidelines. Newborn babies need quite small amounts of formula and more frequent feeds to start with, usually around 6 to 8 feeds in 24 hours for the first few weeks. Slowly increase the quantity (size) of each feed during the day. Feed your baby when they show signs that they want it. Babies tend to feed little and often, so they may not finish their bottle. Having a big feed doesn't mean your baby will go longer between feeds.


In general, a hungry baby will let you know when they are ready to be fed. They will show signs of nuzzling, sucking (on fingers, on your shoulder, at the air), or mouthing (opening their mouth and turning their head). These early signs are useful when you and baby are learning to feed. Try to feed your baby whenever they show signs that they are hungry.

Crying is considered a late sign of hunger, so ideally, you'll learn baby's earlier cues over time. Try to feed your baby before they start crying. It’s easier to feed when they are not upset and crying.


(KidsHealth NZ, 2013)

Your baby is getting enough formula if they are content and settled for a couple of hours after a feed, gaining weight at a steady rate and having 6 or more very wet nappies every day.

(KidsHealth, NZ, 2017)

To prepare the formula you need formula powder, clean water, a jug with measuring marks (for measuring water to add to the powder) and feeding bottles and teats with caps, collars and sealing discs. Always boil and cool tap water before using it.  

There are a variety of feeding bottles and feeding teats available. When choosing bottles, those with straight sides and wide necks are best, as these are the easiest to clean. When choosing a teat, check the label information to make sure it has the right flow rate for your baby’s age. 

(KidsHealth, NZ, 2017)

There are a variety of feeding bottles and feeding teats available. The following is a guide of things to think about when buying bottles and teats.

Choosing feeding bottles

You will need at least three large bottles with leak-proof caps, discs and teats. Choose bottles with straight sides and wide necks. Bottles should be smooth on the inside surface (no ribbing or indentation), as these are the easiest to clean. Choose bottles with clearly marked measurement guides that will not wear off over time. Glass bottles are easier to clean than plastic but break more easily. ‘Disposable’ bottles have throw away liners only. 

Choosing feeding teats

When choosing teats, be aware that teats differ in flow rate and shape.

Flow rate

Check the information on the label of the teat to make sure it has the right flow rate for your baby’s age. For newborn babies, choose teats with one hole in the tip of the teat to give a slow flow to encourage strong sucking. For older babies, you may use teats with more than one hole to give a faster flow. Formula should drip from the teat at the rate of about one drop per second when tipped. To test the flow, hold the bottle upside down and milk should drip out at a constant, steady rate. If it drips too slowly, your baby will get tired before finishing their feed. If milk pours out in a stream, your baby may dribble and splutter and will not enjoy the feed. A baby should take 15 to 30 minutes to drink a bottle.


There is no evidence that any particular shape of teat is preferred. Many manufacturers claim that their teats are an exact copy of a mother’s nipple in her baby’s mouth, but there is no proof that any teat design is the best. Orthodontic teats are no better than regular-shaped teats and they may, in fact, not be good for later tooth development. Over time, you will discover which teat works best for your baby. Air bubbles should rise through the milk as the baby drinks. If the teat flattens during feeding, loosen the cap a little.

Read the information on the formula tin carefully (including the use-by date) and follow the instructions. Make sure you use the scoop that comes in the tin. Infant formula powder is not sterile. Handle and store prepared formula with care to keep it safe for your baby. Formula should be made just before use. If this is not possible, prepared formula may be stored at room temperature for no more than 2 hours or in the fridge for no more than 4 hours. For your baby’s first 3 months, all water used for formula should be boiled and cooled on the day you use it. In cities and towns, you can use water straight from the tap to make formula after your baby is 3 months old. Otherwise, continue to boil the water. 

(KidsHealth, NZ, 2013)

Preparing water for formula

Babies, especially newborns, are at risk of infection. Tap water can be a source of bugs which can lead to infection. To reduce this risk, you can take precautions by using boiled and cooled water to prepare your baby's formula. Boiling water will kill all disease-causing bugs. This is especially important in the first 3 months.

Your baby's age What to do?
0 to 3 months Boil and cool all water used for formula, including:
  • tap water
  • filtered water
  • commercially available bottled water.
Do this on the day it is used.
Older than 3 months You can use the town supply water from the cold tap to make baby’s formula. Run the tap for 10–15 seconds before you fill the bottle.
  • If you are concerned about water quality, use boiled and cooled water until baby is 6 months old.
  • Water from tanks or bore holes should be boiled until baby is 18 months old. 

When making up formula, pour the correct amount of water into the sterilised bottle before adding the powder. (Not all baby bottles have accurate volume lines on them. To check that your bottles do, look for the standard mark EN14350 on the bottle or packaging, or take your bottles to a pharmacy and ask a staff member to check if the bottles are accurate.)

In an emergency, if you are unable to boil water, you can use water purification tablets (such as Aquatabs). Follow the instructions on the packet. 

Babies, especially newborns, are at risk of infection so you must wash and sterilise all feeding equipment properly until your baby is at least 3 months old. This includes any items used with breast milk.

(KidsHealth, NZ, 2017)

How to clean feeding equipment 

To clean feeding equipment you will need warm soapy water, a bottle brush and a teat brush. Fill the sink with warm soapy water. Use the bottle brush to clean the bottles inside and out. Use the teat brush to clean the teats inside and out. Wash any other items used (eg, bottle caps, kitchen tongs, measuring jug). Make sure you remove all traces of milk when cleaning the bottles and teats. Rinse everything well in hot water and leave them to air dry.

How to sterilise feeding equipment

To sterilise the bottle and teats you will need sterilising equipment, which can be either:

  • a large cooking pot (large enough for water to cover everything in it) with a lid
  • special sterilising solution (or tablets) and a large plastic container with a lid
  • a steam sterilising unit designed for microwave sterilising or an electric steam steriliser.

If sterilising by boiling, fill a large pot with water. Place all the washed items in the water, ensuring that no air is trapped and everything is covered with water. Put the lid on and heat the water until it comes to a rolling boil. Turn the stove off and keep the pot covered until you need the items. When you need to make up a feed, wash and dry your hands thoroughly and use the sterilised tongs to lift items out of the pot. If you remove items before you need them, cover and store them in a clean place, with the bottles assembled with a teat inside and a lid on.

Follow the manufacturer’s instructions when using steam (in an electric or microwave steam steriliser) or chemicals (sterilising tablets or solution) for sterilising.

Feeding is great bonding time with your baby.  It should be an enjoyable and social experience for you both. Holding your baby close while you are feeding them is an opportunity to give them love and cuddles.

(KidsHealth, NZ)

  • Hold your baby close to your body, facing you, when feeding. Hold your baby in the bend of your arm – it may be more comfortable to switch arms mid-feed.
  • Keep your baby nearly upright – this helps to prevent ear infections caused by the formula flowing into the middle ear.
  • Hold the bottle at an angle so that the formula fills the teat and bottle neck.
  • Your baby needs time for sucking the bottle, looking at and listening to you, and enjoying skin-to-skin contact. Holding your baby close while you are feeding them is an opportunity to give love and cuddles. Do not leave your baby lying with a bottle to suck on – if your baby falls asleep with milk in their mouth, the milk can damage their teeth.
  • Take the bottle away as soon as your baby has had enough. Do not put your baby to bed with a bottle to feed alone. This is dangerous because your baby may choke. Also, older children who are regularly fed this way are more likely to get middle-ear infections and tooth decay.

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