How Much Formula by Age

Why the answer depends on which country you ask

Search for formula volumes and you will find confident tables. What you will not find is one table that every health service agrees on, because the three big English-language guidances answer the question in three different units.

The NHS answers it by refusing. Its formula milk page opens with the line that newborns "need quite small amounts of formula to start with" and that "the amount will vary from baby to baby", then moves straight on to hunger cues and nappies. There is no NHS volume chart. That is a deliberate editorial choice, not an oversight: NHS bottle-feeding advice states plainly that "your baby will know how much milk they need" and tells you not to worry if they do not finish the bottle.

Ireland's HSE does publish numbers, and it does so by weight. The Irish table gives 150ml per kilogram of body weight per day from birth to six months, split over six to eight feeds a day in the first three months and four to six feeds a day from four to six months. The HSE labels this "a guide only" and asks you to speak to a public health nurse if your baby is taking a lot more or a lot less.

The American Academy of Pediatrics publishes numbers per feed and per pound. Both approaches are defensible. Neither is a target your baby has agreed to.

The figures, side by side

The AAP's per-feed figures

The AAP's schedule is the most granular of the three. In the first week after birth, babies should be taking "no more than about 1 to 2 ounces (30 to 60 ml) per feed". Across the first month that rises gradually to 3 to 4 ounces (90 to 120 ml) per feed, amounting to around 32 ounces a day, usually every three or four hours. By six months, the AAP expects 6 to 8 ounces (180 to 240 ml) at each of four or five feeds in 24 hours.

The AAP also offers a weight-based rule of thumb: about 2.5 ounces (75 ml) of formula a day for every pound (453g) of body weight. That works out close to the Irish 150ml per kilogram, which is reassuring given they were derived separately.

The CDC's frequency figures

The CDC gives frequency rather than daily totals. In the first days of life it suggests offering 1 to 2 ounces every two to three hours, and notes that "most infant formula-fed newborns will feed 8 to 12 times in 24 hours". Over the first weeks and months that settles to roughly every three to four hours, and from six to twelve months most babies need formula or solid food about five or six times in 24 hours.

What happens after solids start

The Irish staged guidance is the clearest here. Between six and nine months it puts formula at three to four feeds a day, roughly 600ml in total. Between nine and twelve months it drops to a maximum of 400ml a day, because solid food is doing more of the work. The CDC frames the same shift differently: as your baby gradually eats more solid food, "they will gradually need less infant formula".

The ceiling everyone agrees on

There is one number all three broadly share, and it is an upper limit rather than a goal. The AAP states that a baby "should usually drink no more than an average of about 32 ounces (960 mL) of formula in 24 hours", and adds that if your baby consistently seems to want more or less than the expected range, that is a conversation for your doctor rather than something to solve with a bigger bottle.

The AAP is also blunt about why: "sometimes patterns of obesity begin during infancy, so it is important not to overfeed your baby". Babies with a strong urge to suck may be looking for comfort rather than calories.

Reading the baby, not the tin

Every one of these sources ends up in the same place. NHS Best Start in Life describes responsive or on-demand feeding as the recommended approach: "you do not need a feeding schedule", and "never force your baby to finish the bottle". The hunger signs it lists are worth learning, because they arrive before crying does. A baby getting ready to feed will often try to find something to suck, usually their hands or fingers, move their eyes around, root for the teat, start wriggling, or open and close their mouth. Crying is a late signal, and a baby who is already upset is harder to feed.

The same page makes the practical point that this is also the protection against overfeeding: feeding your baby when they are hungry, rather than on a clock, reduces the risk.

How to tell the amount is right

The NHS gives output measures rather than input measures, which is the more useful test. Your baby should have around six wet nappies a day from a few days after the birth, wet with clear or pale yellow urine, or feeling heavy. After the meconium of the first day or two, they should be passing pale yellow or yellowish-brown poo, at least one a day in the first week.

Weight is the other check. Healthy babies in the UK are weighed at birth, again in the first week, and after that only at 8, 12 and 16 weeks and again at one year, with the results recorded in the red book. Weighing more often than that does not make the picture clearer; it usually just makes normal day-to-day variation look alarming.

Things that quietly distort the numbers

Two habits skew intake in opposite directions. Adding extra scoops makes the feed more concentrated and, in the NHS's words, "can make your baby constipated or dehydrated". Adding extra water dilutes it, and the CDC warns that too much water "may mean the formula would not meet the nutritional needs of your baby". Neither is a way to adjust how much your baby gets. The way to adjust that is the number of millilitres of correctly-made-up feed you offer.

The other distortion is the bottle itself. Formula-fed babies tend to take larger, less frequent feeds than breastfed babies, and a big feed does not, as the NHS points out, mean your baby will go longer before the next one.

When to ask someone

Speak to a midwife, health visitor, public health nurse or GP if your baby is consistently taking far more or far less than the ranges above, if weight gain has stalled, if wet nappies have dropped off, or if feeds have become distressing. If your baby is under eight weeks and has not passed a stool for two to three days, the NHS asks you to raise it, particularly if weight gain is slow.