This article is about serving temperature — how warm the bottle should be when your baby drinks it. The temperature of the water you mix the powder with is a different question with a different answer, and it matters for safety. We cover that separately below.
There is no single correct serving temperature for baby formula. Some babies like it warmed, others are happy to drink it cool. The right temperature is the one your baby will actually drink. What matters is that the bottle was made up safely, that it is not hot enough to burn, and that your baby gets the nutrition they need.
Warm or cold?
Warming a bottle makes sense to most of us. It is often what we saw our own mothers do, and since breast milk does not arrive chilled, it feels natural to offer formula at a similar warmth.
For a lot of babies, milk at roughly body temperature — around 98.6 °F (37 °C) — is ideal, especially for babies switching between breast and bottle. Newborns in particular are often comforted by a bottle that feels close to breast milk. If you are struggling to get your baby to accept a bottle, getting it close to 37 °C is worth trying.
But some babies do not mind a cooler bottle and some seem to prefer one. Plenty of parents find a cool bottle goes down more easily while a baby is teething.
Once your baby is eating solids and drinking water, they usually become far less fussy about temperature. A baby who would only take warmed formula as a newborn is often perfectly happy with a room-temperature bottle a few months later.
The HiPP tin gives the same figure for serving: let the made-up bottle cool to drinking temperature, about 37 °C, and check it before you feed.
The water you mix it with is a separate question
This is where this article used to give bad advice, so it is worth being exact.
An earlier version of this page said that water cooled to around 120 °F “kills any potential bacteria in the formula”. That is not correct, and we have removed it. The US Centers for Disease Control and Prevention states that powdered infant formula is not sterile and can carry germs such as Cronobacter, and that “very hot water (around 158°F/70°C) is needed to kill these germs”. 120 °F is about 49 °C, which is nowhere near that.
Health Canada is specific about when the 70 °C method applies.
For healthy, full-term babies, Health Canada says: “Boiled water that has been cooled to room temperature can be used to prepare powdered infant formula.” Serve it as soon as possible after making it.
For babies who were premature or low birth weight, are under two months, or have a weakened immune system, Health Canada says to boil the water for two minutes, cool it to 70 °C — about thirty minutes — and mix the formula at that temperature, because “maintaining water at 70 °C kills potential harmful bacteria”. Health Canada also recommends that babies in this group drink commercially produced sterile liquid formula rather than powder where possible.
The HiPP tin asks for water cooled to about 40–50 °C before you add the powder. For a healthy, full-term baby, Health Canada’s room-temperature allowance is a floor rather than a ceiling, so the tin’s warmer figure does not put you outside that guidance.
One more thing Health Canada notes, and it is worth knowing if your baby is on a specialist formula: some powdered formulas cannot be prepared with water at 70 °C because of heat-sensitive ingredients, and in those cases it says to “consult and follow the advice from your doctor or health professional”.
Making bottles ahead: what we got wrong
This page used to say you could make up bottles for the day in the morning and warm them as needed. That skipped the conditions Health Canada attaches, and the conditions are the whole point.
Health Canada does permit made-ahead bottles, but only prepared the way it describes for higher-risk infants: water boiled for two minutes and cooled to 70 °C, then the bottle cooled quickly under cold running water, refrigerated at 4 °C or below, and used within twenty-four hours or as specified by the manufacturer. A bottle made with 40 °C water and left in the fridge is not the same thing.
The HiPP tin does not offer a made-ahead option at all. It says to make each bottle just before the feed and to have it drunk within half an hour.
We have written up how long formula keeps — in the tin, once opened, and once made up in full.
How to warm a bottle
The easiest way is an electric bottle warmer. Some have a universal fit, others are made for one brand of bottle, so check before you buy.
Without one, a bowl of hot water works in about five minutes. Health Canada’s guidance is to warm for no more than fifteen minutes — the longer a bottle sits warm, the more opportunity bacteria have to grow. Away from home, most cafes will help you out with a jug of hot water.
Always test a few drops on the inside of your wrist, where the skin is more sensitive, before you feed. It should feel lukewarm, not warm.
Never warm a bottle in the microwave. It creates pockets of high heat that can scald a baby’s mouth. The HiPP tin says the same thing.
And do not refrigerate and reuse a bottle you have already warmed.
How to cool a bottle
If your baby prefers a cooler bottle, standing it in a bowl of iced water brings the temperature down in minutes — faster than the fridge, which matters with a hungry baby.
Common questions
What temperature should formula be when I feed it?
Around 37 °C (98.6 °F) suits most babies, and that is the figure printed on the HiPP tin. Some babies are happy with room temperature or cooler. Test it on the inside of your wrist first — lukewarm, not warm.
What temperature water do I mix the powder with?
A different question. The HiPP tin says 40–50 °C. Health Canada permits boiled water cooled to room temperature for healthy, full-term babies, and 70 °C for premature, low birth weight, under-two-month or immunocompromised babies, and for any bottle made ahead.
Can I make up bottles for the whole day?
Only using Health Canada’s method: 70 °C water, rapid cooling under cold running water, fridge at 4 °C or below, used within twenty-four hours. The HiPP tin does not sanction made-ahead bottles at all.
How long can a bottle sit out once my baby has started drinking?
Health Canada says two hours, then discard the rest. The HiPP tin says the bottle should be drunk within half an hour of being made. US guidance is stricter again: the CDC says to use prepared formula within two hours of preparation and within one hour from when feeding begins.
Can I warm a bottle in the microwave?
No. Microwaves heat unevenly and create hotspots that can burn your baby’s mouth.
Sources and references
Health Canada and CDC fetched and read 18 September 2026. HiPP 1 BIO Combiotik tin, 800 g, Dutch-language pack code NL/472-03, photographed 12 September 2026.
- Health Canada, Preparing and handling powdered infant formula
- Health Canada, Recommendations for the preparation and handling of powdered infant formula
- Centers for Disease Control and Prevention, Infant Formula Preparation and Storage