Is it safe to eat seafood after 4 days? A nutrition and food safety guide

October 22, 2025 •

4 min read

Over 50% of foodborne illness cases linked to seafood are due to improper handling, emphasizing the importance of correct storage. So, is it safe to eat seafood after 4 days? The answer depends heavily on the type of seafood and how it has been stored.

Quick Summary

The safety of consuming refrigerated seafood after four days hinges on whether it was raw or cooked, the storage conditions, and specific type. Adhering to strict guidelines is crucial to prevent illness.

Key Points

Risky after 4 days: Consuming raw seafood stored in the refrigerator for four days is highly risky; cooked seafood is also likely unsafe unless held under perfect conditions.
Know the signs of spoilage: Rely on your senses—a strong, fishy or ammonia-like odor, a slimy feel, or a milky appearance are clear indicators the seafood is no longer safe.
Practice strict cold storage: Always keep seafood at or below 40°F (4.4°C) to slow bacterial growth, and never leave it out for more than two hours.
Use freezing for long-term storage: If you don't plan to cook seafood within 1-2 days, freeze it. For best quality, consume raw frozen fish within 3-8 months.
Cook thoroughly: Ensure all seafood reaches an internal temperature of 145°F (63°C) to kill most harmful bacteria, though some toxins from improper handling remain unaffected.
Prevent cross-contamination: Separate raw seafood from other foods, and thoroughly wash all surfaces and utensils after handling.
Discard if uncertain: When in doubt about freshness, discard the seafood to prevent potential foodborne illness.

The Science Behind Seafood Spoilage

Unlike other types of meat, seafood is highly perishable due to its unique biological composition. The deterioration process begins immediately after a fish is caught, and it’s a race against time to preserve its quality and safety. The primary culprits behind spoilage are enzymes and bacteria. Once the fish dies, natural enzymes begin to break down its components, while bacteria that were normally kept in check during the fish's life start to thrive.

This rapid spoilage is exacerbated by temperature. The "Temperature Danger Zone"—the range between 40°F (4.4°C) and 140°F (60°C)—is where bacteria multiply most rapidly. Seafood should not be left in this zone for more than two hours. Even within a refrigerator set below 40°F, bacterial growth is only slowed, not stopped. This is why the shelf life of fresh seafood in the fridge is so short.

Dangers of Eating Spoiled Seafood

Consuming seafood that has gone bad can lead to serious foodborne illnesses. One of the most common is scombroid poisoning, which occurs when certain fish—like tuna, mackerel, and mahi-mahi—are not properly refrigerated. This leads to a buildup of histamine, which is not destroyed by cooking. Symptoms resemble an allergic reaction and can include flushing, headache, itching, and diarrhea.

Other seafood poisonings, such as paralytic shellfish poisoning, are caused by toxins from algae that accumulate in shellfish like mussels, oysters, and clams. These toxins are also heat-stable, meaning cooking does not make them safe. Symptoms can range from gastrointestinal issues to neurological problems, and in severe cases, can be fatal. This is why it is crucial to know the signs of spoiled seafood before it's too late.

How to Tell if Seafood is Bad

Even with a date stamp, sensory evaluation is a critical final defense. Here’s what to look for:

Smell: Fresh seafood should have a mild, oceanic scent. As it spoils, it develops a strong, fishy, sour, or ammonia-like smell that becomes more intense over time. The ammonia odor is a strong indicator of spoilage, and cooking will not eliminate it.
Appearance: For whole fish, fresh eyes are clear and shiny. Cloudy, dull, or sunken eyes are a sign of age. Fresh fillets are moist and slightly translucent. Spoiled fish can develop a milky, slimy film or discoloration, often with a grayish or bluish tint.
Texture: Fresh fish flesh should be firm and spring back when pressed gently. If the flesh feels mushy, soft, or leaves an indentation when you press it, it's a strong sign of spoilage. For shellfish like clams and mussels, shells should be tightly closed; if they gape open and do not close when tapped, the animal is dead and should be discarded.

Maximizing Seafood Shelf Life Through Proper Storage

If you don't plan to cook your seafood within the recommended one to two days, freezing is the best option for long-term storage. For refrigerated storage, these practices are essential:

Temperature: Maintain your refrigerator at or below 40°F (4°C).
Packaging: Store seafood in airtight containers to prevent cross-contamination and odor absorption. For raw fillets, placing them on a bed of ice in a shallow, perforated pan within a larger tray can help keep them extra cold while allowing meltwater to drain away.
Live Shellfish: Keep live shellfish like mussels and clams in a bowl covered with a damp cloth, as they need air to breathe. Do not store them in airtight containers or water.
Freezing: Wrap seafood tightly in moisture-proof plastic wrap and then foil to prevent freezer burn. Label and date packages. Most frozen seafood is best consumed within 3 to 8 months for quality, though it remains safe indefinitely. Never refreeze thawed seafood.

Refrigerated Seafood Storage Timeline


Seafood Type	Maximum Recommended Storage in Fridge	Key Signs of Spoilage
Raw Fish Fillets	1–2 days	Strong fishy or ammonia smell, slimy film, mushy texture, milky or grayish color
Cooked Fish	3–4 days	Strong, foul odor, dry texture, mold
Raw Shrimp/Scallops	1–2 days	Strong odor, slimy appearance, discoloration
Cooked Shrimp	3–4 days	Pungent odor, slimy texture
Live Mussels/Clams	2–3 days	Unpleasant odor; shells that are open and don't close when tapped
Live Oysters	Up to 10 days, if stored properly	Dry or sunken appearance, offensive smell; shell doesn't close when tapped
Live Crab	1 day (or up to 4 if from a reputable local source)	Strong, foul smell

Safe Preparation and Cooking

Properly thawing and cooking seafood is the final step to ensure safety. The safest method for thawing is to move the seafood from the freezer to the refrigerator overnight. For a faster method, place the sealed seafood in a bowl of cold water, changing the water every 30 minutes. Never thaw seafood on the counter.

Cook seafood to an internal temperature of 145°F (63°C), which kills most harmful bacteria. Signs of doneness include:

Fish: The flesh becomes opaque and flakes easily with a fork.
Shrimp, Scallops, and Lobster: The flesh becomes firm and pearly white or opaque.
Shellfish (Clams, Mussels, Oysters): The shells open during cooking. Discard any that remain closed.

When in Doubt, Throw it Out

When it comes to food safety, especially with highly perishable items like seafood, trust your senses and err on the side of caution. Even if you've stored it properly, if something smells or looks off after four days, it's not worth the risk of a foodborne illness. Good nutrition relies on eating safe, high-quality food. Following these guidelines will ensure you can enjoy the many health benefits of seafood without compromising your health.

For more in-depth information on food safety, you can consult the official FoodSafety.gov website.

Frequently Asked Questions

Raw fish should only be kept in the refrigerator (at 40°F or below) for a maximum of one to two days before being cooked or frozen.

Cooked seafood can be safely stored in the refrigerator for up to three to four days. Beyond this point, the risk of spoilage and potential foodborne illness increases.

Scombroid poisoning is caused by high levels of histamine that build up in certain types of fish, like tuna and mackerel, when they are not properly refrigerated after being caught. Histamine is not destroyed by cooking.

Obvious signs of spoilage include a strong, pungent fishy or ammonia-like smell, a slimy coating on raw fish, mushy texture, and discoloration or a milky color in the flesh.

A mild, ocean-like smell is normal for fresh fish. However, if the smell is strong, sour, or pungent, it indicates spoilage and the seafood should not be consumed, even after cooking.

If you don't plan to eat leftover cooked seafood within three to four days, it is best to freeze it in an airtight container. Freezing can maintain quality for up to three months.

Live oysters with their shells closed can be refrigerated for 7-10 days if stored properly on ice with a damp cloth. However, shucked oysters only last 3-5 days in the fridge. Always check for a fresh, briny smell and shells that close when tapped.

Freezing halts the growth of bacteria, but it doesn't always kill them. This means that once thawed, bacteria can become active again and begin to multiply. It is vital to cook thawed seafood promptly.