‘Best By’ vs. ‘Use By’: What you need to know about food dating

“Best-By” vs. "Sell-By" vs. "Use-By"? What's the difference, and how do you know when food is no longer safe to eat? Food dating labels can be confusing.

Sept. 16, 2021

By Isabel Brown, Consumer Watchdog Associate

In the midst of a crisis, whether it’s a hurricane, wildfire or public health emergency, it’s essential to be as prepared as possible to make sure you and your family stay healthy and safe. As people brace themselves for future weather emergencies and climbing cases of COVID-19, many may be concerned about the accessibility of basic amenities including food. 

“Best-By” vs. “Sell-By” vs. “Use-By”? What’s the difference, and how do you know when food is no longer safe to eat? Whether you’re stocking up or are left with the items in the back of your cupboard, it’s important to know how long food products will stay fresh and when they expire.

With the exception of baby formula, food dating is not required by federal regulations. Because it is not federally required, food dating is not standardized, meaning that many of the dates we find stamped on food containers aren’t as accurate as we think. 

Food dating labels are confusing. There are several ways that food products are dated, and different labels mean different things. This guide can help you understand the difference between commonly used food dating labels so that you can make sure that you and your family are well-stocked with safe food.

Understanding Food Dating

First, it’s important to understand the difference between “closed dating” and “open dating.” Closed dating consists of a series of numbers and/or letters that tell the day the product was made and is usually used on boxed or other non-perishable items that can be stored at room temperature. Some closed dating labels, like the one pictured below, are easier to understand than others.

Open dating is easier for consumers to read and understand. It shows a day and month (and year for frozen and non-perishable items) along with a phrase explaining what the date means (like “Best-By, “Use-By,” or “Sell-By”). Open dating is usually used on meat, dairy and other perishable products.  

Here’s a breakdown from the federal Food Safety and Inspection Service of what the most common open dating labels mean:
  • A “Best if Used By/Before” date indicates when a product will have the best flavor or quality. It is not a purchase or safety date.

  • A “Sell-By” date tells the store how long to display the product for sale. It’s for inventory management. It is not a safety date.

  • A “Use-By” date is the last date recommended for the use of the product while at peak quality. It is not a safety date except for when used on infant formula.

  • A “Freeze-By” date indicates when a product should be frozen to maintain peak quality. It is not a purchase or safety date.

“Pack dates” on eggs and other poultry products are another form of food dating. Egg cartons labeled with a USDA grade shield, for example, must be marked with a three-digit number of the day of the year they were washed and packaged. Eggs packed on the first day of the year (Jan. 1) are marked with 001, and eggs packed on the last day of the year (Dec. 31) are marked with 365. 

Some egg manufacturers also include “Best-By” dates on cartons. This isn’t the same as an expiration date. Eggs kept in their original packaging, and the coldest part of your fridge should stay safe to eat for three to five weeks after purchase, even after the “Best-By” date has passed.

What This Means for Consumers

Most of the dates you find printed on food refer to its quality rather than its safety. Many people and even grocery stores assume that a “Best-By” date is the same as the expiration date, even though food often is still perfectly safe past the printed date. This creates an enormous amount of food waste. And it’s made even worse when the dates themselves aren’t based on science.

Some states are trying to fix this broken system. For example, a new law in Pennsylvania changed the process for determining dates on milk. Until recently, all dairy products sold in Pennsylvania were labeled with a “Sell By” date that is 17 days after production. The new law lets producers put more accurate dates on specific products. This means that the labeled dates are based on science — not an arbitrary window of time. But this is only one kind of food product in one state. 

The USDA estimates that more than 30 percent of the food supply is lost or wasted at the retail and consumer levels. In some states you can’t even donate food that has passed its “Sell By” date, even if it’s still safe and nutritious. This trend is incredibly wasteful for non-perishable food, including many items in emergency food pantries that people rely on after natural disasters. 

Some manufacturers print “Best-By” dates on bottled water even though water can keep indefinitely if stored properly. Unopened packages of white or wild rice can keep for two years in your cupboard. Canned foods like meat and vegetables can keep for three to five years, despite what labels say. Remember, the dates are about optimal quality, not safety. The FoodKeeper App from FoodSafety.gov is helpful for understanding exactly how long specific food items are safe to keep unopened and after opening. 

Knowing When Food Has Spoiled

Because food dating has more to do with freshness than safety, it’s up to you to decide when food has expired or spoiled. After checking the FoodKeeper App, you can tell by:

  • Misshapen packaging: Contamination can cause food packages to bloat as a result of bacteria releasing gas. Dented cans or other abnormal packaging suggests contamination or that the item is no longer properly sealed, meaning bacteria can enter. Jarred items have safety lids that pop up if the seal has been broken. Examining the packaging is the first step in making sure your food is safe to eat.

  • Hissing or fizzing upon opening: Some canned or jarred foods release a hissing or loud popping sound when they are opened. This is normal for products that have been vacuumed-sealed. However, if spurts of air or contents of the container explode out of the package when it is opened, it can indicate contamination. A fizzing sound or frothy discharge can occur if a product has fermented due to bacteria. If this happens, take a closer look at the product to see whether there are other symptoms of contamination. Do not consume food that may be spoiled.

  • Smell: Spoiled food can have an “off” or putrid odor that indicates the presence of bacteria or other contamination that could make you sick if you eat it. A foul smell is often the most tell-tale sign that your food is not safe to eat.

  • Color: Contamination can alter the color of food or create spots or layers of discoloration where bacteria or mold is growing. The colors of different bacteria vary greatly, so anything out of the ordinary should be taken as a sign that the food is no longer safe for consumption.

  • Texture: Curdled milk or dairy products are examples of how contamination can change food texture. Spoiled food products can become lumpy, chunky or mushy if they have been contaminated. It’s important to know what your food should look like and throw it out if the texture has changed.

  • Taste: Relying on taste to determine whether something has gone bad should be the last resort. You should inspect potentially spoiled food first by smelling it and looking at it before tasting it. Some bacteria can make you sick after only ingesting a small amount, while contamination like bread mold is less toxic. Expired food can taste rotten or fermented. If your food tastes spoiled, spit it out and throw it out. If you ingest contaminated food, watch for symptoms of food-borne illness and contact emergency health services if symptoms become severe.

Food can be a source of comfort during emergencies, and it’s essential to be an informed consumer. Better education about food dating labels could keep more than a half a million tons of food from getting thrown out. Nationally standardized date labeling could push that total to closer to 1 million tons. In the meantime, understanding how long your food is safe to eat is vital for limiting food waste and making sure you and your family have enough to eat, especially in times of crisis. For more information, refer to the CDC, FDA and USDA.