What happens if you eat best before eggs? A guide to safety and freshness

September 30, 2025 •

5 min read

According to the U.S. Department of Agriculture (USDA), refrigerated eggs are safe to eat for three to five weeks after the "pack date," regardless of the "best before" or "sell by" date. So, what happens if you eat best before eggs? For most properly stored eggs, very little, as these dates are indicators of quality, not necessarily safety.

Quick Summary

This article explores the safety of eating eggs past their 'best before' date, explaining the difference between quality and safety dates. It provides reliable tests to check for freshness and outlines the risks associated with truly spoiled eggs, including bacterial contamination like Salmonella.

Key Points

'Best Before' is for Quality, Not Safety: The 'best before' date on an egg carton indicates peak freshness and quality, not when the egg becomes unsafe to eat.
Eggs Last Longer with Proper Storage: Refrigerated eggs can be safe to eat for 3–5 weeks after the Julian pack date, even if the 'best before' date has passed.
Use the Float Test for Freshness: Very fresh eggs sink and lay flat in water, older but safe eggs stand upright, and spoiled eggs float and should be discarded.
Trust Your Nose and Eyes: A foul, sulfurous smell or discoloration like a pink or iridescent white are definitive signs of a spoiled egg and necessitate disposal.
Cook Eggs Thoroughly for Safety: To kill potentially present bacteria like Salmonella, cook eggs until both the yolk and white are firm.
Store Eggs in the Coldest Part of the Fridge: Keeping eggs in their carton on an inside shelf, not in the door, minimizes temperature fluctuations and preserves freshness.

Understanding the 'Best Before' Date vs. 'Use By' Date

Many consumers mistakenly believe that a "best before" date is an expiration date, but this is a common misconception that contributes significantly to food waste. In reality, these labels serve different purposes and carry different implications for your health.

Best Before / Best if Used By: This date is a manufacturer's recommendation for when a food will be at its peak quality in terms of flavor, texture, and nutritional value. It is not an indicator of safety. For properly stored eggs, it is often safe to eat them for several weeks beyond this date. The quality may diminish—the egg white might become thinner, and the yolk flatter—but this doesn't automatically mean the egg is unsafe.
Use By: This is a much stricter date, typically found on highly perishable foods. A "use by" date indicates the last day the product is expected to be at peak quality and freshness. However, for eggs specifically, the USDA states that even with a "use-by" date, refrigerated eggs are generally safe for 3–5 weeks after being purchased, as long as they are stored properly at or below 40°F (4°C).

How to Determine Egg Freshness Post-'Best Before'

Since the date on the carton isn't the sole determinant of safety, you can use your senses and a few simple tests to check if an egg is still good.

The Float Test

One of the most reliable and oldest methods for checking egg freshness is the float test. As an egg ages, its porous shell allows air to pass through, causing a small air cell inside to grow larger over time.

To perform the test:

Fill a bowl or glass with cold water.
Gently place the egg inside.
If the egg sinks and lies flat on its side, it is very fresh.
If it sinks but stands upright on one end, it's older but still safe to eat. The larger air cell at the top makes it stand up. These eggs are actually ideal for hard-boiling because the larger air pocket makes them easier to peel.
If it floats to the surface, it's likely too old and should be discarded. The large air cell makes it buoyant. While some sources say it might still be safe, the quality is severely diminished, and it's best to err on the side of caution.

The Sniff and Visual Test

If the float test gives you mixed results or you just want to be extra careful, a simple visual and sniff test is highly effective. A bad egg will emit a distinctive, foul, sulfur-like odor that is unmistakable.

Here’s how to check:

Before cracking: Hold the egg close to your nose and give it a quick sniff. If you detect any unpleasant odor, toss it immediately.
After cracking: For an extra layer of safety, crack the egg into a separate bowl before mixing it with other ingredients. This prevents a single bad egg from contaminating an entire recipe.
Inspect the inside: Look for discoloration. The egg white should be clear or slightly cloudy, and the yolk should be round and compact. If the egg white is pink or iridescent, it indicates spoilage from Pseudomonas bacteria and should be thrown out. A runny, watery white is a sign of an older egg, but not necessarily a spoiled one.

Comparison of Fresh vs. Older Eggs


Feature	Fresh Egg	Older Egg (Beyond 'Best Before')
Appearance (Cracked)	Yolk is firm, round, and high. White is thick and stands up around the yolk.	Yolk is flatter and less round. White is thinner and spreads out easily.
Smell	Neutral, clean smell.	May develop a faint sulfur smell over time. A strong, rotten smell is a sign of spoilage.
Float Test	Sinks to the bottom and lies flat on its side.	Sinks but stands upright. Very old eggs will float.
Usage	Ideal for all culinary purposes, especially poaching and frying where a firm shape is desired.	Great for baking, scrambling, or hard-boiling, as the air pocket makes peeling hard-boiled eggs easier.

The Risks of Eating a Truly Bad Egg

While eating an older, but not spoiled, egg is usually harmless, consuming a truly bad egg carries significant health risks. The most dangerous of these is contamination by Salmonella bacteria.

Salmonella Contamination: Salmonella can be present on the outside of an eggshell or, less commonly, inside the egg itself from an infected hen. Symptoms of a Salmonella infection, or salmonellosis, typically appear 12 to 72 hours after consuming a contaminated egg and include fever, diarrhea, abdominal cramps, and vomiting. While most healthy individuals recover within a few days, the infection can be more severe in young children, older adults, and those with weakened immune systems, sometimes requiring hospitalization.
Preventing Salmonella: To minimize risk, always keep eggs refrigerated at 40°F (4°C) or colder. Discard any eggs with cracked shells, and cook all eggs until the yolks and whites are firm. Using pasteurized eggs for dishes that require raw or lightly cooked eggs, such as hollandaise sauce or Caesar salad dressing, is also a recommended precaution.

Storing Eggs Correctly to Maximize Freshness

Proper storage is critical for extending the life of your eggs and ensuring safety. The USDA recommends storing eggs in their original carton in the coldest part of the refrigerator, not the door. The door's temperature fluctuates every time it is opened, which can speed up spoilage. The carton also provides an extra layer of protection from temperature changes and prevents the porous shells from absorbing strong odors from other foods.

Conclusion

Ultimately, eating properly stored, older eggs past their "best before" date is generally safe, provided they pass a few basic freshness checks. The "best before" label is a quality guideline, not a safety deadline. Relying on the float test, your nose, and your eyes is the most effective way to judge an egg's usability. However, if an egg is truly rotten, the risk of foodborne illness from bacteria like Salmonella is real, making it crucial to discard any eggs with a foul smell or other signs of spoilage. By understanding the difference between date labels and practicing good food safety, you can confidently use your eggs while minimizing unnecessary food waste.

This article provides general information and is not a substitute for professional medical advice. Always consult a healthcare provider with questions about food safety or if you experience symptoms of foodborne illness.

Frequently Asked Questions

If properly refrigerated at 40°F (4°C) or colder, eggs can typically be safe to eat for three to five weeks after the Julian pack date printed on the carton, which is often several weeks past the 'best before' date.

Yes, but not necessarily because of the date itself. The risk of food poisoning, especially from Salmonella, comes from consuming a truly spoiled or contaminated egg, which can happen even before the 'best before' date if the egg was mishandled or improperly stored.

The most reliable methods are a combination of the water float test and the sniff test. If an egg floats or has a foul, sulfurous odor when cracked, it is likely spoiled and should be thrown out.

An egg floats because its internal air cell has grown large enough to make it buoyant. This is a clear indicator that the egg is quite old and should be discarded, as its quality is compromised and it may be spoiled.

A cloudy egg white is a good sign; it indicates that the egg is very fresh. As eggs age, the cloudy carbon dioxide dissipates through the shell, and the white becomes clearer.

Yes, older eggs with a thinner white are often preferred for baking because the less viscous white is easier to incorporate into batters. As long as they pass the smell test, they are fine to use.

For maximum freshness and safety, store eggs in their original carton on an inner shelf of the refrigerator, not the door. The carton protects them, and the consistent temperature on the shelf is ideal.