A 3-month-old on formula typically takes 4 to 6 ounces per feed, 5 to 6 times a day — about 24 to 32 ounces in 24 hours.
Age is a rough guide. The number that actually governs the amount is weight, and the two disagree often enough to be worth checking.
By age
| Age | Per feed | Feeds / 24h | Daily total |
|---|---|---|---|
| Newborn (0–1 wk) | 1–3 oz | 8–12 | 16–24 oz |
| 2–4 weeks | 2–4 oz | 7–9 | 20–26 oz |
| 1–2 months | 4–5 oz | 6–8 | 24–30 oz |
| 3 months | 4–6 oz | 5–6 | 24–32 oz |
| 4–5 months | 5–7 oz | 5–6 | 28–32 oz |
| 6 months | 6–8 oz | 4–5 | 28–32 oz |
| 7–9 months | 7–8 oz | 3–4 | 24–30 oz |
| 10–12 months | 7–8 oz | 3 | 20–24 oz |
Two things in that table surprise people.
The daily total stops rising at around six months. It plateaus near 32 oz and then falls as solids take over. A ten-month-old drinking less than a four-month-old is following the pattern, not falling behind it.
The per-feed amount keeps climbing while the feed count drops. Larger meals, fewer of them. That is the whole shape of the first year.
By weight — the number the ranges come from
The rule the age table is built on:
About 2.5 ounces of formula per pound of body weight per 24 hours, up to a ceiling of roughly 32 ounces a day.
| Weight | Daily total |
|---|---|
| 8 lb | 20 oz |
| 10 lb | 25 oz |
| 12 lb | 30 oz |
| 13 lb and up | 32 oz (the ceiling) |
A large 3-month-old at 15 lb does not need 37 oz. The ceiling holds. Past roughly 32 oz a day, more formula displaces the iron and variety that solids will start providing, and it is the point at which most paediatric guidance says to stop adding.
A small 3-month-old at 10 lb needs about 25 oz — the low end of the age range, and entirely normal.
Breastfed babies do not work this way
The numbers above are for formula, where the volume is visible and countable.
A breastfed baby regulates intake by feeding to satiety, and typical intake sits around 25 oz a day from one to six months with very little change over those months, because breast milk composition shifts as the baby grows.
Expressed milk given by bottle follows the breastfed pattern, not the formula pattern: roughly 1 to 1.5 oz per hour since the last feed, and it does not scale up the way formula volumes do.
What actually tells you it is enough
Volume is the least reliable signal. Three better ones:
Nappies. Six or more wet ones in 24 hours after the first week.
Weight gain along a curve. Not a specific number — a consistent line. Which percentile matters far less than staying near the same one, and that is what the growth chart is for.
Behaviour at the end of a feed. Turning away, slowing, relaxed hands. A baby draining every bottle and immediately wanting more may be on a bottle nipple that flows too fast to register fullness.
When the numbers mean something
Ring your paediatrician or health visitor if there are fewer than 4 wet nappies a day, if feeds are consistently under half these ranges for several days, or if weight crosses downward through two percentile lines on the chart.
Never dilute formula to stretch it, and never concentrate it to add calories. The mixing ratio on the tin is a medical instruction — the electrolyte balance depends on it, and getting it wrong is dangerous in both directions.
Sources: American Academy of Pediatrics, Amount and Schedule of Baby Formula Feedings; World Health Organization child growth standards; NHS Infant formula: common questions.
This page reproduces published feeding guidance for general reference. It is not medical advice and does not replace your paediatrician, who knows your baby's growth history.