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    How to warm baby bottles

    Cold milk. Screaming baby. Classic 3am combo. Here's the lowdown on warming bottles safely and quickly — because nobody has time to guess.

    Auteur: Sophie | Feeding Category Manager

    Posté le : 4 Mar, 2026

    Temps de lecture : 4 min

    Why do we heat baby bottles? And what's the best way to warm them safely and quickly?  

    We’ve written this simple guide to answer all your bottle-warming questions.  

    Why should you heat a baby's milk? 

    If you're formula feeding, it's recommended that you make up a fresh bottle for every feed using hot water that’s at least 70°C so that bacteria found in the formula powder is killed. But also, babies just like their milk warm.  

    When babies are breastfed, breast milk is naturally at body temperature (36.5–37.5°C), so they usually prefer milk that's warmed to body temperature when they're feeding from a baby bottle. 

    So, are baby bottle warmers worth it? Well, warm milk is also easier for a baby to digest (because they don't need to use extra energy to warm it up in their tummy) and some parents find that warm milk is less likely to give their baby stomach aches.  

    What's the difference between the Tommee Tippee LetsGo warmer and the PrepGo formula maker?

    Both products are designed to make feeding on the go more manageable, so your choice depends on whether you want to warm pre-prepared feeds or need to prepare fresh formula from scratch while out and about.

    • Choose the LetsGo Portable Warmer: If you need a convenient, travel-friendly solution to warm bottles while on the move. It is designed for warming pre-prepared bottles of expressed breast milk or ready-made formula when you're away from home. It's made for on-the-go parents who need a convenient solution to warm bottles without access to boiling water.
    • Choose the PrepGo Formula Feed Maker: If you're looking to prepare fresh formula feeds safely and quickly when you're away from home. It Prepares fresh formula feeds by combining boiling water with formula powder and cooling it to the right temperature. It's made for parents who need to prepare fresh formula feeds safely while on the move.

    How to heat a baby bottle 

    Use an electric bottle warmer 

    Using a specially designed baby bottle warmer is the easiest way to heat a bottle of breast milk or ready-made formula.  

    They warm bottles gently to preserve nutrients (meaning no dangerous hot spots), are fast and easy to use and take the guesswork out of warming baby's bottles. Just make sure the bottle warmer you choose is suitable for the types of baby bottles you have, and always follow the instructions. 

    Use warm tap water 

    Fill a jug or bowl with warm tap water. The water should be hot enough to heat the bottle, but cool enough so that you can place your hand in it. 

    Place the bottle in the warm water for no more than 15 minutes. Once the bottle is warmed, swirl it gently to make sure all the milk is warmed evenly, but avoid shaking as this can introduce air bubbles. mum holding baby and bottle

    What not to do when warming a baby bottle

    Don't use boiling water 

    There's no need to boil water to warm a baby's bottle. Remember, you're just trying to gently warm the milk inside to body temperature.  

    Don't use a microwave 

    Don't heat your baby's milk in a microwave. Microwaves don't always heat evenly, so even if your baby bottle feels okay on the outside, there can be hot spots in the milk that could scald your baby's mouth. And overheating breast milk destroys the nutrients it contains. 

    It's safer to use a baby bottle warmer or some warm tap water to heat your baby's bottle. 

    How to check for the perfect temperature 

    Have you ever wondered why people pour milk from their baby's bottle on their wrists to test the temperature? It's because the skin on the inside of your wrist is thin and sensitive, just like your baby's, so this serves as a reliable guide.  

    It should feel warm (not hot or too cold).  

    Choosing the bottle (and teats) you want to use

    There are lots of different baby feeding bottles to choose from, and what kind you choose is very much up to you (and your baby).  

    Some babies will prefer the feel of a particular teat and you may have to try a few before you find the one that's best for you. 

    If you're transitioning from breastfeeding to bottle feeding, a teat that feels and moves like a breast should make the switch easier. Tommee Tippee bottle teats have a special breast-like shape that encourages a natural latch.  

    Baby bottles can be made from glass, plastic, or silicone. If you're using plastic bottles, check that they're BPA-free (all Tommee Tippee bottles are). And always check the manufacturer's instructions for cleaning, sterilising and warming your chosen bottle. 

    Frequently asked questions

    Yes, breast milk comes from the body at a temperature of around 36.5–37.5°C. So if you've cooled breast milk to store it or if you're making up a bottle of formula, it should be served to your baby at around the same temperature. 

    Yes, they can. There's no harm in giving your baby formula that you haven't warmed up, but babies tend to prefer their milk warm.  

    Breast milk contains tryptophan, a substance that encourages the brain to produce the sleep hormone melatonin, so this may make a baby feel sleepy after a feed. Tryptophan can also be found in baby formula and dairy products. 

    Plus, warmed milk is easier for babies to digest, meaning there's less chance of discomfort and tapped wind at bedtime. 

    Yes, it is possible to overheat a bottle of baby milk, and this can cause dangerous hot spots to form which could burn baby’s mouth.  

    Overheating breast milk destroys the nutrients it contains. And rapidly heating and then cooling baby bottles can also cause baby bottles to become misshapen or damaged, which can encourage bacteria to grow inside. 

    You should always use warmed milk to feed your baby immediately and never reheat it.  

    Bacteria can form in any milk (especially when a baby’s saliva gets into it when they’re feeding), which is why you should not warm, refrigerate and then reheat any milk that you give to your baby. 

    No. Heating baby milk in the microwave isn't recommended. Microwaves can heat milk unevenly, creating hot spots that could burn your baby's mouth. It's safer to warm milk in a bottle warmer, under warm running water, or in a bowl of warm water. This ensures a more even temperature throughout and is much safer for your baby.

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