A 3-month-old typically drinks 4 to 7 ounces per feeding, with most babies consuming roughly 24 to 32 ounces total over 24 hours. The exact amount depends on whether your baby is breastfed or formula-fed, how much they weigh, and their individual appetite.
The Weight-Based Rule for Daily Intake
The most reliable way to estimate how much milk your baby needs is based on body weight. On average, infants need about 2.5 ounces of formula or breast milk per day for every pound they weigh. A 12-pound 3-month-old, for example, would need roughly 30 ounces spread across the day. A smaller baby at 10 pounds would need closer to 25 ounces.
This calculation gives you a ballpark, not a strict target. Some days your baby will drink more, some days less. Growth spurts, which are common around 3 months, can temporarily push intake higher for a few days before things settle back down.
Feeding Size and Frequency
Formula-fed 3-month-olds generally take 4 to 5 ounces per bottle every 4 to 5 hours, which works out to about 6 to 8 feedings per day. By the later end of 3 months and into month 4, some babies move toward 6 to 7 ounces per bottle with five to six feedings in 24 hours. The shift is gradual: as your baby’s stomach grows, they take more at each sitting and go longer between feedings.
Breastfed babies follow a different rhythm. Breast milk digests faster than formula, so breastfed 3-month-olds typically eat more frequently, sometimes every 2 to 3 hours, with 8 to 10 nursing sessions across a full day. Individual sessions may be shorter, and it’s harder to measure exact ounces at the breast. If you’re pumping, expect to offer around 3 to 4 ounces per bottle, since breast milk is absorbed more efficiently than formula and your baby doesn’t need quite as much volume per feeding.
How to Tell If Your Baby Is Getting Enough
Counting ounces matters less than reading your baby’s signals. Hunger cues at this age include putting hands to their mouth, turning their head toward the breast or bottle, and puckering or smacking their lips. Clenched fists are another early sign. When your baby is full, they’ll close their mouth, turn their head away, and visibly relax their hands.
These cues are more reliable than any formula on a chart. Feeding should be responsive, meaning you offer the bottle or breast when your baby signals hunger and stop when they show signs of fullness. Forcing a baby to finish a bottle, even one with breast milk, can lead to overfeeding and unnecessary weight gain over time. If your baby consistently drains every bottle and still seems hungry, it’s fine to offer a little more. If they regularly leave an ounce behind, make slightly smaller bottles to reduce waste.
Steady weight gain and 6 or more wet diapers a day are the clearest signs your baby is eating enough overall.
Night Feedings at 3 Months
At this age, many babies start consolidating their sleep into one longer stretch of 4 to 5 hours at night. That’s a noticeable improvement from the newborn weeks, when babies wake and feed overnight with the same frequency as during the day. Most 3-month-olds still need at least one or two night feedings, though. A baby who sleeps a 5-hour stretch and then wakes to eat is following a completely normal pattern.
Night feedings count toward total daily intake, so a baby who eats well overnight may take slightly less during the day, and vice versa. There’s no need to wake a healthy, gaining 3-month-old to feed unless your pediatrician has specifically asked you to.
Signs You May Be Overfeeding or Underfeeding
Overfeeding is more common with bottle-fed babies because milk flows more easily from a bottle than a breast. Signs include frequent, large spit-ups after every feeding, gassiness and visible discomfort, and weight gain that’s tracking well above your baby’s growth curve. If you notice these patterns, try pacing the bottle by holding it more horizontally, pausing partway through, and letting your baby set the speed.
Underfeeding shows up as fussiness that doesn’t resolve after a feeding, fewer than 6 wet diapers in a day, and weight gain that stalls or drops off. A baby who seems unsatisfied even after finishing a full bottle may be ready for a slightly larger serving. Increasing by half an ounce at a time is a simple way to test whether they need more without overshooting.
Every baby’s appetite is different, and weekly fluctuations are normal. What matters is the trend over weeks, not any single feeding or single day.