Only Santa Claus has the immune system to handle a million glasses of milk that have been sitting out all night. The rest of us need to make sure we drink cold, fresh milk by the expiration date.
In a nutshell, to best avoid a stomach ache or worse:
- Don’t leave milk out at room temperature for over an hour.
- Place the milk in the fridge as soon as you get home after grocery shopping or receiving the delivery.
- Keep it cold. It’s tempting to leave the carton or jug of milk out if you might be getting a second bowl of cereal, but all the times it starts to warm up, it shortens its shelf-life.
- Store the milk on the bottom shelf or at the back of your refrigerator (not on the side of the door, where warm air reaches it easily when you open the door).
- This applies to most nondairy milk too, such as oatmilk, coconut milk, soy and almond milk.

Is shelf life the same for all types of milk?
Before checking whether your milk has gone bad, know its type. Each type of milk comes with a different shelf life. For example, reduced-fat milk and skim milk are known to last for 7 days.
On the other hand, whole milk can turn sour in 5 days. Similarly, non-fat milk and lactose-free milk have a shelf life of around 10 days.
Nondairy Milk Storage at Room Temperature
Nondairy milk, such as soy, almond, coconut, and oat milk, can also spoil when left out. If they are shelf-stable (UHT-processed and unopened), they can remain safe for weeks or months at room temperature. However, once opened, these milks must be refrigerated and should follow the same two-hour safety window as dairy milk. If nondairy milk smells sour, appears curdled, or has a strange taste, it’s best to discard it.
Where to store milk in the refrigerator
Unlike France, Spain, and other European countries where drinking ultra-high temperature (UHT) milk is the norm, pasteurized milk is common in the US. According to the FDA, it is necessary to refrigerate pasteurized milk.
A food safety expert from Clemson University claims that you need to maintain a temperature of at least 45°F for Grade-A milk. Keep the milk on your refrigerator’s bottom shelf for the best results (it’s usually the coldest area in the fridge).
How long can unopened milk sit out?
The FDA asserts that you should never keep unopened milk out of the refrigerator at room temperature for more than two hours. However, this window reduces as the temperature rises.
This means that when the temperature exceeds 45°F, milk is at risk of harboring bacteria that is reproducing in the warming environment. Cycling through cool and room temp will cause the milk to go “bad” faster, so as soon as you are done serving milk from its original container, put it immediately back in the refrigerator.

How long does milk last after it is opened?
After opening a bottle of milk, you can expect it to last well for four to seven days after the label date has passed. However, this duration is only valid if you refrigerate the milk properly.
How long does organic milk last?
Once opened, both organic and non-organic milk have a similar shelf life of 7-10 days, provided they are stored at or below 40°F. Claims that you can drink organic milk for a month only apply to unopened UHT-pasteurized organic milk.
WANT TO SAVE THIS RECIPE?
Why does organic milk last for so long?
You may have noticed that many cartons marked as “Organic” milk have a longer shelf life than “regular” milk, sometimes a full month longer. But its longevity isn’t because of the label–the process used for pasteurizing is something called UHT, or ultra-high temperature processing.
According to Scientific American, the non-organic milk uses standard pasteurization, which doesn’t kill all the bacteria that UHT does.
How long can raw milk last in the refrigerator?
Raw (unpasteurized) milk can last 7-10 days in the refrigerator if stored properly at a temperature of 36-38°F. Raw milk spoils faster than pasteurized milk because it naturally contains bacteria. If stored at temperatures above 40°F, the bacteria, particularly lactobacilli, multiply quickly and convert lactose (milk sugar) into lactic acid, giving the milk a tangy flavor as it spoils. Ideally, raw milk can last 7-10 days if stored at a temperature of 36-38°F. Higher temperatures allow natural bacteria, like lactobacilli, to produce lactic acid, which gives spoiled milk its tangy flavor. To ensure freshness and safety, raw milk must be kept cold and consumed promptly.
Temperature Control: Keeping raw milk as close to 36°F as possible significantly slows bacterial growth.
Taste of Spoiled Raw Milk: The tangy or sour flavor comes from lactic acid fermentation, caused by the activity of natural bacteria in raw milk.
Safety Concerns: Spoiled raw milk should not be consumed, as harmful bacteria like Listeria, E. coli, or Salmonella may also proliferate.

Is there any milk that can last for more than a month?
Yes, UHT milk, also called long-life milk or shelf-stable milk, fits the bill. This milk is heated in extremely high temperatures (275°F) for 2-4 seconds and it also comes in unique packaging. When unopened, it can last for six months at room temperature.
However, don’t expect any miracles after it is opened. Once opened, it has the same shelf life as that of standard milk. [iii]
How long can you leave whole milk in the cup of a toddler?
You may have handed a young child a cup of milk, only to find the cup untouched when you find it under the couch later.
According to some healthcare professionals, if milk is left out for less than two hours, then it is still safe for drinking. However, this is your little child in question. Adults usually have better immune systems, so they may be able to take risks with these threshold limits.
But when it comes to kids, extreme caution is recommended. So to be safe, if you find your toddler’s cup of milk out even after an hour, pour it out and wash the cup.

The bottom line
You may not get deathly ill after taking a swig of spoiled milk, but it is still better to be careful than to take any risk. As a rule of thumb, adopt these habits:
- Don’t leave milk out for more than an hour.
- Place the milk in the fridge as soon as you get home after grocery shopping.
- Keep the milk on the bottom shelf of your refrigerator and/or at the back (not in the side of the door, where warm air reaches easily when you open the door).
Remember, Santa’s been at this gift-giving game for centuries. He’s got a stomach of steel and a heart full of joy. But let’s not test his immune system; fresh treats make for a jollier Saint Nick!