Last updated on October 16th, 2025 at 07:06 pm

Ever looked at a lapsed best by date and wondered if your food was suddenly unsafe? These dates that we’ve been conditioned to treat as law are, in reality, simply guidelines. In fact, 84% of consumers admit to discarding food near the printed expiration date—even though, if handled properly, eating food past these labels is not necessarily dangerous and won’t automatically make you sick. The purpose of these dates is to indicate quality, not safety. (The only exception is infant formula).

Misunderstanding these labels contributes to massive food waste every year. Read on to understand what best by, sell by, and use by dates really mean—and why it’s often perfectly okay to ignore them.

Why is it important to understand food dating?

According to the FDA, 20% of all wasted food can be attributed to confusion over expiration dates. This contributes to the serious problem that food waste presents: nearly 40% of all food produced is discarded, making it the largest category of waste (25%) in landfills. And it isn’t the agricultural industry, grocery stores, or restaurants who are the biggest contributors–it’s consumers.

Wasted food obviously has financial implications for you, but also for our country. In the U.S., the financial loss from food waste amounts to about 2% of our nation’s GDP. For the average consumer, one survey found that each person spends an average of $1500 per year on discarded food. I’m sure you could find something else to use that money for!

Food waste also accounts for 10% of all greenhouse gas emissions. The UN states that if global food waste was a country, it would be the third largest contributor to greenhouse gas emissions in the world, after the US and China.

Learn more about the consequences of food waste and strategies to decrease your contributions here.

How to read expiration dates on food

There is no universal set of descriptions for food product dating, which varies between manufacturers. According to the USDA, these are the common phrases. Note that none of them pertain to safety.

‘Best by’ date

• Best By Date meaning: This date is meant to indicate to consumers when a product will be at its best flavor or quality. It is not indicative of safety.

‘Use-By’ date

• Use By Date meaning: Very similar to ‘best-by’ date. This is last date recommended for using a product while at peak quality. It is not a safety date–except when used on infant formula.

‘Sell-By’ date

• Sell By Date meaning: The purpose of ‘sell-by’ is to direct stores on how long to display products for sale for inventory management. It is not a safety date. Typically, one-third of a product’s shelf-life remains after the sell-by date for the consumer to use at home.

‘Freeze-By’ date

• Freeze By Date meaning: Indicates when a product should be frozen to maintain peak quality. It is not a purchase or safety date.

Interpreting the numbers on egg cartons

Egg cartons have their own dating system. Those with the USDA grade shield on them must display the “pack date” (the day that the eggs were washed, graded, and placed in the carton). This number is a three-digit code that represents the consecutive day of the year starting with January 1 as 001 and ending with December 31 as 365. Super helpful, right?

When a “sell-by” date does appear on a carton bearing the USDA grade shield, the code date may not exceed 30 days from the date of pack.

Any other dates will be listed in a MMDDYY format, where “MM” refers to the month, “DD” refers to the date, and “YY” refers to the year.

If you’ve noticed a bunch of other numbers printed on food packaging, this is most likely a lot code. Each batch of products are given a lot code, and their purpose is to enable the tracking of product in interstate commerce. These codes also enable manufacturers to rotate their stock and locate their products in the event of a recall, as well as help consumers identify whether foods are part of a product recall.

Expiration dates explained

Best by, sell by, and use by dates are chosen by manufacturers. There is no universal set of descriptions of food dating, and besides infant formula, product dating is not federally regulated; systems can even vary between states.

A joint report between The National Resource Defense Council (NRDC) and Harvard states that, “For the vast majority of products, manufacturers use their own methods to determine the length of shelf life and the dates to list. Some use lab tests, others use literature values, and yet others use product turnover rates or consumer taste testing.”

Additionally, they might take into account factors like the length of time and the temperature at which a food is held during distribution and offered for sale, the characteristics of the food, and the type of packaging when determining the labeled dates. Whichever method is utilized, the dates chosen are on the conservative side.

In retail, some product will approach or pass the date label while on shelves. Some states restrict the sale of products after the date on the label has passed, even though the majority have no safety risk associated with the date. Consumers are also not willing to pay full price for items that they perceive to have less shelf life.

How long past expiration date is food still safe to eat?

It depends on the food, but in general, trust your senses. If it looks, smells, and tastes ok, it is most likely just fine to eat. Humans have long survived without dates printed on meals.

Baking Ingredients & Spices

According to America’s Test Kitchen, an opened bag of refined white flour should be good for about one year. After that, the quality may begin to deteriorate and the flour may take on an unpleasant flavor and scent. Other flours with a higher fat content, such as almond flour, may go bad twice as fast.

Leavening ingredients like baking soda and powder don’t really go bad, but do lose their potency and effectiveness. Dried herbs and spices are the same; old spices won’t be unsafe to eat but the added flavor to foods will be underwhelming.

Canned

The USDA says that high-acid canned foods (e.g. tomatoes and fruits) will keep their best quality for 12 to 18 months. Can linings might discolor or corrode when metal reacts with high-acid foods but as long as the can is in good shape, the contents should be safe to eat, although the taste, texture and nutritional value of the food can diminish over time.

Low-acid canned foods (everything else) will keep for two to five years.

Processed

Ultra-processed foods have a very long shelf life, well beyond expiration dates. This is, of course, due to multiple stabilizers, preservatives, and other additives included in these foods. It’s best for your health–and possibly the planet’s–to avoid these foods as much as possible.

Frozen

Frozen foods can usually be eaten indefinitely, they just won’t taste as good as they get older, especially if they have freezer burn, which affects quality but not safety.

Dairy

There are no set recommendations when it comes to dairy products. Most research suggests that as long as it’s been stored properly (ideally at 38-40 degrees F).

• Unopened milk generally stays good for 5–7 days past its listed date, while opened milk lasts at least 2–3 days past this date.
• Yogurt should be ok for 1-2 weeks after the listed date.
• Cheese is ok until it gets moldy. Mold can be sliced off of hard cheeses; the inside will still be safe to eat.

Eggs

Eggs are good for about a month in the refrigerator.

Meat & Poultry

Meats are definitely one product you want to be careful on and stick close to the dates.

Condiments/salad dressing

Commercial salad dressings are usually high in acidic ingredients like vinegar, and so can be refrigerated indefinitely, the exception being dairy-based dressings like blue cheese. Condiments in general should be ok longer than the dates as long as they pass the sniff test.

Check out the USDA’s Foodkeeper app, which has a directory of food storage dates.

How to tell if food is spoiled

Produce

Produce is probably the easiest to tell when it’s no longer edible. If there’s a funky smell, a significant change in color or texture, or the presence of mold, it should be thrown out.

Meat & Poultry

Color change isn’t necessarily an indicator when it comes to meat. Some color change is normal as myoglobin in the meat interacts with the air. (Read the answers to common questions regarding meat color.)

• Fresh meat will spring back when pressed on; if it’s older, it may have lost its firmness.
• Meat and poultry shouldn’t have a strong smell, so if a strong odor is present, they should be disposed of.
• If the texture is slimy or sticky, that’s also a good indicator that it shouldn’t be consumed.
• If you’ve already cooked the meat and notice a bad flavor that’s not cooking-related, such as sour or tangy, stop eating and toss.

Leftovers

The USDA says leftovers can be kept in the refrigerator for 3 to 4 days, and a maximum of 7 days. Store appropriately, and use your senses along with this chart.

Canned & Packaged goods

Canned foods should be thrown out if they have large dents (enough to put your finger in), are leaking, bulging, rusted, or have a foul odor. Jars or any other containers that are cracked, have loose or bulging lids, or spurt liquid when opening should be discarded.

Refer to the USDA’s shelf stable food storage chart for specific storage guidelines and answers to common safety questions.

Dairy

The best way to determine whether milk or yogurt is spoiled is with a simple sniff test.

Eggs

There are several tests you can do to determine whether eggs are still good. Try a float test and place the egg in a bowl of water. If the egg floats, it has gone bad and should be discarded. The freshest eggs lie horizontally on the bottom of the bowl, while older ones start to tilt upward. If it is standing upright and still at the bottom, it is past its prime but still safe to use.

Food storage

Proper storage of food items is key to maximizing their shelf life. Take time to learn the best way to store different foods, as there are many factors to consider. Produce is the most wasted type of food, so proper storage is especially key.

Utilize your freezer. Many items freeze well: produce, meats, leftovers, even cheese. If you’re not going to be able to get to leftovers soon enough, pop them in the freezer. I love this FoodSaver Vacuum Sealing System. The vacuum seal prevents freezer burn, making for long-lasting foods.

Learn other food preservation techniques, such as canning, dehydrating, or freeze drying. Your local state university extension service is a great source of information and offer free/inexpensive courses such as these from Utah State University.

Final thoughts on expiration dates

Treating labeled dates on food as guidelines, rather than hard and fast rules, is a crucial aspect of decreasing food waste and saving money. Don’t throw things out just because the printed dates have passed. Trust your senses to tell you whether something is safe or not. Of course, don’t take unneccesary risk and when in doubt, throw it out. But if the smell, appearance, texture, and taste are acceptable, food should be safe to eat.

In the meantime, support organizations that have long tried to accomplish the passing of a standardized labeling system. The Food Date Labeling Act is the current work in progress, reintroduced in May 2023.