Milk is often still good for several days after its sell-by date, because the USDA says a sell-by date is for store inventory and is not a safety date. As long as the milk has stayed refrigerated at 40°F (4°C) or below and smells, looks and tastes normal, it is fine to drink; once opened, plan to finish it within about 7 days.
The exact number of days varies with how the milk was handled, how cold your fridge is and when you opened it. Here is how to judge it.
What the Date on Milk Actually Means
Milk cartons in the US carry one of several phrases: "Sell By," "Best If Used By," "Use By" or simply a date. According to the USDA Food Safety and Inspection Service (FSIS), none of them is a federal safety deadline for milk:
- Sell-By tells the store how long to display the product for inventory management. It is not a safety date.
- Best If Used By indicates when the product will have its best flavor or quality.
- Use-By is the last date recommended for peak quality. FSIS notes it is only a safety date on infant formula.
Federal law does not require date labels on most foods, infant formula being the exception. Some states set their own dating rules for milk, which is why labels differ from state to state.
The key line from the USDA: if the date passes during home storage, a product (other than infant formula) should still be safe and wholesome if handled properly, until signs of spoilage are evident.
How Long Is Milk Good After the Sell-By Date?
There is no official number of days, because the date itself is not a safety cutoff. What determines how long milk lasts is how it has been stored since it left the dairy.
| Milk situation | Refrigerator, 40°F (4°C) or colder | Freezer, 0°F (-18°C) |
|---|---|---|
| Unopened, past the sell-by date | Good until it shows signs of spoilage; check it daily | About 3 months |
| Opened | About 7 days | About 3 months |
| Buttermilk | 1 to 2 weeks | About 3 months |
| Left out over 2 hours (1 hour above 90°F / 32°C) | Discard | Discard |
Refrigerator and freezer times come from the FoodKeeper guide developed with Cornell University and USDA. The 2-hour rule comes from FDA and USDA guidance for all perishable foods.
In practice, an unopened carton that went straight from the store to a cold fridge often stays fresh for several days past its sell-by date. A carton that rode home in a hot car or lives in the fridge door will turn sooner.
Pro tip: Keep milk on an interior shelf, not in the door. The door warms up every time you open the fridge, and milk is one of the most temperature-sensitive things you buy.
How Long Is Milk Good After Opening?
Once you open a carton, bacteria from the air, your glass and your hands get in. FoodKeeper guidance is to use refrigerated milk within about a week. That clock runs from when you opened it, not from the printed date, so a carton opened two days before its sell-by date and a carton opened two days after will both last roughly a week from opening, assuming normal fridge temperatures.
A few habits help opened milk last:
- Pour what you need and put the carton straight back. Don't leave it on the table during breakfast.
- Never pour leftover milk from a glass back into the carton.
- Close the cap tightly so the milk doesn't absorb fridge odors.
- Write the opening date on the cap or log it somewhere. This is the one date the carton doesn't tell you.
Ultra-pasteurized and shelf-stable milk
Ultra-pasteurized (UHT) milk is heated to a higher temperature, so unopened cartons last much longer than regular pasteurized milk, and shelf-stable aseptic cartons can sit in the pantry until opened. Once opened, treat both like regular milk: refrigerate and follow the package directions.
How to Tell If Milk Has Gone Bad
According to FSIS, spoiled food develops an off odor, flavor or texture because of naturally occurring spoilage bacteria. For milk, that means:
- Smell: sour or unpleasant. This is the fastest and most reliable check.
- Texture: lumps, curds or a thick, slimy consistency.
- Color: yellowish tinge instead of white.
- Carton: a bulging container is a sign of gas from bacterial growth.
- Taste: if it passes the first four checks, a small sip will tell you. Sour means it is done.
If any of these show up, pour it out, regardless of the date. If the milk looks and smells normal past its date, it is generally fine to drink.
What about milk that tastes slightly off but isn't sour?
Milk can pick up "fridge" flavors from strong foods like onions or leftovers, especially if the cap is loose. That flavor is a quality problem, not a safety one. Sourness, curdling and a bad smell are the signs that matter.
Can You Freeze Milk Before It Expires?
Yes. If you won't finish a carton before it turns, freeze it. FoodKeeper guidance puts frozen milk at about 3 months for best quality.
- Pour a little out first: milk expands as it freezes and can split the carton.
- Thaw it in the refrigerator, never on the counter.
- Shake it well after thawing. The fat separates during freezing, so thawed milk can look grainy. It works best in cooking, baking, smoothies and coffee.
For whole milk, buttermilk and plant-based milks, see our complete guide on whether you can freeze milk. For butter, cream and other dairy, read how to freeze butter and dairy.
Make Milk Last Longer
Most early spoilage comes down to temperature. A few changes make a big difference:
- Check your fridge temperature. The FDA recommends 40°F (4°C) or below and suggests using an inexpensive appliance thermometer, because the built-in dial is not always accurate. Our guide to fridge and freezer temperatures explains how to check.
- Shop for dairy last. Pick up milk at the end of your trip and take it straight home.
- Pick from the back. Stores rotate stock, so cartons with the latest dates are usually at the back of the shelf.
- Buy the size you finish. A gallon that goes sour costs more than a half-gallon you use up.
Pro tip: Use milk that is close to its date in recipes that cook it: pancakes, sauces, mashed potatoes, oatmeal. Cooking does not fix sour milk, but it is a good way to finish a carton that is still fine.
FAQ
How long is milk good after the expiration date?
If it has been kept cold and is unopened, milk is usually fine for several days after the date on the carton, and the USDA says it should stay safe until spoilage is evident. Always smell and look before drinking. Once opened, use it within about 7 days.
Is it safe to drink milk after the sell-by date?
Yes, if it smells and tastes normal. FSIS says the sell-by date is for store inventory and is not a safety date. Spoiled milk is easy to detect by its sour smell and texture.
How long does milk last after opening?
About 7 days in a refrigerator at 40°F (4°C) or colder, according to FoodKeeper guidance. Keeping it on an interior shelf rather than in the door helps.
What happens if you drink milk that has gone bad?
A sip of sour milk usually causes nothing more than a bad taste. Drinking spoiled milk can cause stomach upset, so if milk smells sour or has curdled, throw it away. For symptoms of foodborne illness, contact a healthcare provider.
Does the expiration date on milk apply after opening?
Not really. After opening, the opening date matters more than the printed date. Count about a week from when you opened it.
Track the Date That Matters
The printed date tells you when the store should sell the milk. It doesn't tell you when you opened it. Logging the opening date in Freezer Inventory Tracker, with a reminder a few days later, is a simple way to finish milk before it sours, and it helps the whole household know which carton to use first. For more fridge staples, read how long eggs last in the fridge and how to store potatoes and onions.