6+ Reliable Ways to Warm Formula & Breastmilk On the Go

I may receive a commission for purchases made through product links on this page, but I always stand by my opinions and endorsements!

When it comes to food, baby’s earliest days are, quite frankly, a bit of a nightmare

Breastfeeding is an enormously difficult and tiring job for mom. And formula feeding has plenty of headaches as well.

(You haven’t lived until you’ve forgotten how many scoops of formula you added to an entire jug of the mixture and had to dump the whole thing and start over.)

But whether you’re mixing formula or pumping breastmilk for later use, you’ve probably run into the issue of how to warm milk on the go.

All babies are a little different when it comes to their feeding and burping preferences, and unfortunately, some of them demand that their milk be perfectly heated to their liking!

Not always the most practical thing.

Essentially you have three options: Get by with lukewarm or room temperature when possible, acquire hot water while you’re out and about, or bring extra supplies from home.

Let’s take a closer look at all of the options.


1. Lukewarm or room temperature formula

One of the great benefits of formula feeding is that the formula can be mixed any time, anywhere, and come out fresh and ready to go.

(Once it’s been mixed, however, it’ll need to be finished or refrigerated. Baby formula should never sit out for more than an hour. If it does, or if you’re even cutting it close, toss it.)

But the ability to start that clock whenever you want or need is a nice bonus.

In that case, it’s pretty easy to carry around pre-portioned formula powder and some bottles of water.

That way, if your baby will take the formula at around room temperature, you can mix it whenever you need to. It’s definitely worth letting them try the formula lukewarm, or even cold, and not just assume they don’t like it. (It’s perfectly safe either way.)

If they won’t drink it unless it’s warm, well, there are other options.


2. Get some warm water from a coffee shop or restaurant

Wherever you are, you’re probably never too far from a Starbucks.

(Ah, America.)

Kidding aside, it’s usually not too hard to find a coffee joint, or really any restaurant, that might be willing to give you a free cup of water.

You have a lot of options at this point depending on what kind of milk you’re using and what you have available.

If you’re trying to warm a bottle of breastmilk (or pre mixed and refrigerated formula), you’ll want WARM water and not hot. It’ll take longer to warm, but if the water is too hot it could harm the nutritional integrity of the milk. You may want to lug a little collapsible bowl or something like that to put the water and the bottle in for warming.

If you’re looking for warm water to make fresh formula, again, just be really conscious of the temperature. See if they can give you a cup of half hot / half cold water. Splash a little on your arm before you use it to see if the temperature is right.

Remember to always mix the milk after heating to avoid hot spots or uneven heating.


3. Carry a thermos of hot/warm water from home

Click to see on Amazon

If the idea of asking for hot water from a coffee shop stresses you out, or if you think you might be somewhere more remote with no other options around, you could consider bringing hot water from home in a heavy duty thermos.

Yeti tumblers, for example, can keep things hot (or cold) literally FOREVER. I sometimes get frustrated drinking my morning coffee out of them because it never seems to cool down.

(Check out the Yeti tumbler on Amazon.)

Fill one of those with some hot water from home and you’ll have it at the ready almost all day long if you need it.

(Again, just be very conscious of the temperature of the water when you’re ready to use it. If it’s too hot, don’t use it for fresh formula without cooling it down first, and be careful warming cold milk in water that’s super, super hot.)


4. Use HotHands or other portable warming packs

Click to see on Amazon

You know those little gel packs people use to keep their hands warm at winter football tailgates and while camping?

Those can actually be a great option for warming up bottles in a pinch.

HotHands is a pretty popular brand that people seem to trust, and they come at a fair price. Just crack one open to activate the warming, wrap it around the bottle, and wait a few minutes.

(Check out HotHands warmers on Amazon.)

Warmers like these typically last for hours, so you should be able to make the bottle as warm as you need. Even in the worst case scenario, you should be easily and quickly able to take the chill off of a pre-made bottle, or give a standard bottle of water (for mixing new formula) a little warmth.

It’s not going to be cheap to do this super frequently, so it might not be your top option. But it can’t hurt to keep a couple of these in your go-bag for when you’re really stranded.

(Again, monitor this closely to avoid overheating, and give it a little shake once it’s warmed to avoid hot spots in the milk.)


5. Go to the bathroom and get some hot tap water

Tap water is totally, completely safe to use for mixing fresh baby formula. In fact, that’s what we did for our daughter when she was young. No special filters or anything like that.

Exceptions might be if you live in an area or country where no one should drink the tap water.

The good news is that pretty much no matter where you are, you should have access to a public bathroom.

In there, you can fill up a bottle with warm water (this is even better than the coffee shop ask, because you can control the temperature with the hot and cold knobs yourself) or run a cold bottle of breastmilk under the warm water for a few minutes to take the chill off.

It might not be fun to stand in a public restroom for a few minutes waiting for the water to heat up, then waiting for the milk to warm, but it’ll work if you’re out of other options.


6. Buy a portable bottle warmer

Click to see on Amazon

If you don’t want to futz around with all of this stuff, filling up cups of hot water, standing at the bathroom sink for 5 minutes, etc., you can always invest in a portable bottle warmer.

There are a TON of options available these days.

Some are like little heating pads that wrap around bottles. Others are solid compartments you place the whole bottle inside. Some plug into your car’s A/C adapter. Others plug right into the wall but are small enough to fit into your purse.

(Here’s a super popular portable warmer from Munchkin on Amazon.)

Whatever your needs and budget, there’s probably an awesome portable bottle warmer available for you.


What to do if you overheat the milk

I wrote above that you should be careful not to use water that’s too hot to mix or warm any milk or formula.

There are a few reasons for that.

The biggest one is that, if the milk itself gets too hot, your baby could be in danger of getting burns. That’s obviously a huge problem and something you should avoid at all costs.

The second reason is that when the milk gets too hot, some of its nutrition begins to breakdown.

When all is said and done, though, safety is the primary driver here. If you accidentally overheat the milk when you’re on the go and in a pinch, it’s not the end of the world to let it cool off a bit and still give it to your baby.

It’s not something you should do all of the time, but as long as you’re positive it won’t burn them (splash it on your own arm skin first as a test), the minor degradation of nutrition isn’t the end of the world.


Wrapping Up

Bringing baby out with you, far away from your home bottle warmer, Brita-filtered water, and all the trappings and comforts of home life, can be a little stressful.

But there are plenty of options for you if you need to heat up some milk, or mix some fresh warm formula, away from home.

(Getting them to burp is another story!)

It’s up to you if you’d rather invest in some extras to make things easy, or if you think you’d rather just get by on free hot water from restaurants and bathrooms.

I’ll end with my usual disclaimer: I’m not a doctor. If you have specific questions about what might happen to milk if X, Y, Z happens, ask a professional. I’ve just done my best to compile the most relevant information I could find on the topic.

I hope it helps. Good luck, parents!


Related Questions

Can you warm up premade formula?

Yes, of course!

It’s extremely common and convenient to premake a bottle or jug of formula and heat it up as needed.

Two things to keep in mind, however:

You have to heat it properly. Use a bottle warmer or one of the other methods described above, and never use a microwave which can heat the milk unevenly, cause hot spots, or make it too hot for baby.

Second, don’t heat formula, refrigerate it, and then heat it again. You wouldn’t do this to your dinner, so don’t do it to baby’s food!

How warm should breastmilk be?

There’s no exact temperature that breastmilk or formula have to be. If baby will drink them cold or at room temperature, then that’s just fine!

However, a general rule of thumb is to heat milk to approximately human body temperature (98 degrees or so), which makes sense, right?

When breastmilk first comes out, it’ll be heated by mom’s own internal body temperature. So this is a good goal post to try to emulate if possible.

Always err on underheating vs overheating, however!

Do you have to warm formula?

No, you definitely do not have to warm up formula before feeding it to baby.

Most babies won’t drink cold formula, however, which is why parents often heat it up first. If your baby is fine with cold formula, it’s perfectly safe to use it as-is.