Milk needs refrigeration. But that’s not why you’re here. So let’s talk about how long it can survive without it.

We’ve all been there before, folks.

We get home from the grocery store, and we find ourselves preoccupied with something else.

Maybe we get a phone call from a friend. Maybe we have to tackle a minor emergency. Maybe we are just stressed out—and take what seems like a quick moment to sit down and relax before putting everything away from the shop—only to end up waking up from an hour-long nap.

Before we know it, a decent stretch of time has passed, and we realize that our carton of milk has been left out at room temperature for quite a while.

Is that milk no longer safe to drink? Has it gone bad sitting there on the counter? Am I going to pop the top find a jug of cottage cheese instead of drinking a glass of whole milk?

Decisions, decisions… Find out more right now!

Can You Keep Milk at Room Temperature?

Before we get into “the meat and the potatoes” of how long milk can last at room temperature before drinking it starts to become a health hazard, it’s important to understand that different types of milk have different lifelines, and thus tolerances to room temperature.

Reduced-fat milk and skimmed milk, for example, are some of the more resilient milk options available on the market today. These kinds of milk have the longest shelf life as you will see on the printed date on the carton.

It’s not unusual for a gallon of reduced-fat milk for skimmed milk to still be good to drink for 4-7 days past its expiration date, provided that it has been refrigerated continuously.

Whole milk, on the other hand, is something that you don’t want to fool around with for longer than 1-2 days beyond the expiration date.

The extra fat and cream in that milk get pretty funky in a hurry, turning your milk into a cottage cheese kind of adventure that is anything but delicious (and can probably make you sick, too).

Why are we telling you all of this, you may be wondering?

Because milk with lower levels of fat content will be able to survive at room temperature for longer amounts of time than milk with higher levels of fat content.

Skimmed milk, for example, is going to be a lot more “countertop stable” than whole milk with everything else equal. The details are below.

Two Hours Without Refrigeration is Your Red Line

So, what’s the golden rule when it comes to the safety of milk that’s been left to sit out at room temperature?

According to the U.S. Food & Drug Administration, 1-2 hours of exposure to room temperatures is enough to make any kind of milk (skim, 2%, whole, and such) susceptible to the kind of bacteria you don’t want to be putting into your body.

Obviously, the FDA errs on the side of caution in this department (and for good reason).

In summer, on a sultry day, this time gets shortened to 1-1½ hours since the heat will have raised the average temperature in your kitchen.

Any milk left out for just 60 minutes in a 90°F or hotter room could turn into the funkiest thing you’ve ever tasted if you decided to have a sip. Colder rooms, with an average temperature of 60°F or below, might buy you a bit of extra time.

On a winter’s day, for example, when your kitchen is cooler, you might be able to stretch that window out to 2½ hours or maybe even 3 hours without any ill effects. But you might also be rolling the dice.

It all comes down to your risk tolerance level. Stick to the two-hour rule of thumb, though, and you should be safe.

What About Raw, Unpasteurized Milk?

The milk we buy from the store, also called UHT milk, has been ultra-pasteurized at a higher-than-usual temperature, killing the bacteria that may be harmful or cause it to spoil and effectively prolonging its shelf life.

Raw milk—the kind that, depending on where you live and who you shop from, you can get from a friend who herds cows or a local farmer—is an entirely different animal altogether (no pun intended).

Some farmers say that you can leave raw milk out a lot longer than homogenized and processed commercially available milk, whereas others say it needs to be refrigerated a lot more—and a lot sooner—than commercial milk.

If you are lucky enough to be able to buy raw milk in your area and are comfortable drinking it on a regular basis it’s a good idea to talk to your farmer or supplier for advice.

Still, try to get it into the refrigerator as quickly as possible rather than letting it sit out on the counter. There’s a reason why the Food and Safety Inspection Service at the USDA calls the temperature range from 40°F to 140°F the “danger zone.”

Boil Your Milk to Protect It?

Let’s say, though, that you are going to be without a refrigerator for 24 hours, and need to make sure that your milk stays safe to consume.

Well, in that situation you’re going to want to start boiling your milk every 6 to 8 hours, running up to a hard boil and then letting it cool down all on its own.

This is going to kill off any of the bad bacteria that could have made you sick, but it’s also going to thicken up your milk every time you boil. You might have to add a little bit of water into the mixture to keep the consistency the same.

Just know that flavor and the consistency of this boiled milk concoction is going to be a little off. At the end of the day, though, if you really are up against it and don’t have refrigeration available on a short-term basis, this is a great way to keep your milk safe for consumption.

Does the Milk Pass the Smell Test?

One of the beautiful things about dairy products is that they let you go almost immediately as soon as they start to turn and become unsafe for consumption, putting off a really funky aroma that is unmistakable.

If you open up your jug of milk and noticed that it has that funky kind of stink the next stop for the entire contents needs to be the bottom of your kitchen sink!

Don’t fool around with dairy products that smell funky.

That’s a one-way ticket to the emergency room (at best) and probably a week or more of some really serious digestive issues you won’t forget for the rest of your life.

The Centers for Disease Control and Prevention estimate that 1 in 5 Americans gets sick with food poisoning every year. Of them, 128,000 get hospitalized, and 3,000 die.

If it stinks, pitch it out!

When In Doubt, Toss It Out

Because there are so many ways that dairy can go sideways when exposed to warmer temperatures and left out of refrigerated spaces, it’s not a bad idea to throw any dairy you are nervous about away.

No, it’s never fun to dump a brand-new jug of milk that you paid for down the drain.

But the alternative – that emergency room visit and week of digestive problems we just mentioned – is always going to be a nightmare scenario in comparison.

If you have any doubt about the safety of the milk that got left out for a little bit, flush it down the drain and grab another jug.