How to Tell if Salmon Is Bad

Lindsay D. MattisonUpdated: Mar. 13, 2023

Fillet of salmon fish on white paper closeup

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Do you know how to tell if salmon is bad? Here's a closer look at the telltale signs for both raw and cooked salmon.

As a former restaurant chef, I love cooking salmon. You can make it on the grill, in the oven or on the stovetop, and it’s easy to find complementary side dishes to create a complete meal. Any salmon special I ran at the restaurant always sold out—whether it was pasta, salad or served simply with a side of potatoes and vegetables.

This fish is a great choice for home cooks, too. Fresh salmon is easy to find and packed full of nutrients, but those nutrients fade as the fish ages. Not only that, but spoiled salmon can make you sick! Here’s how to avoid bad salmon.

How to Tell if Salmon Is Spoiled

Expiration Dates

Packaged salmon should always be stamped with a “sell-by” date, so use that as your guideline for when the fish will expire. But if you buy salmon from the butcher counter, it won’t be labeled with a date. Use the USDA guideline instead: Raw salmon is good for up to two days in the refrigerator. Once cooked, the leftovers will last three to four days in the refrigerator.

Smell

It’s a common misconception that fish should smell, well, fishy. Fresh fish has a neutral odor, and that fishy aroma only grows as the salmon sits in the refrigerator. If you open the package and it smells very strongly (especially if it has a sour or ammonia smell), it’s time to toss it out.

Texture

Before cooking your salmon, gently press a finger into the fillet. Fresh salmon feels firm and moist, and the flesh should spring back after you push into it. When you run your hand along the fillet to check for bones, your hand should glide easily without sticking. Sure signs of spoilage are slimy or sticky residues, or if the flesh feels like it will break when you press into it.

Appearance

There are few things as gorgeous as a fresh piece of salmon. It should have a bright pink-orange color with shiny, silver skin (Learn how to remove the skin from salmon). If the salmon’s skin looks dull and lifeless, or if the flesh has faded to gray, it is probably not fresh. Any dark spots or discoloration are indications of spoilage, as is a milky-white residue on the fillet. (Not the white stuff on salmon you see after it cooks, though; that’s safe.)

If you’re lucky enough to find whole salmon, take a look at the eyes. They should be bright and slightly bulging. If they’re sunken or dull, the salmon will taste as sad as those eyes look.

Knowing when to toss out leftover meat and fish is important. Here’s how to know if ground beef has gone bad.

How Long Does Salmon Last?

When buying fresh fish, we recommend making it the last item that hits your grocery cart. You want to keep it as cold as possible, and walking around the room-temperature store can speed up spoilage. Once you get home, get the fish into the refrigerator as soon as possible and plan to use it within one to two days. After fresh fish is cooked, you’ll have a little longer to use those leftovers: three to four days.

If you can’t use salmon by these dates, place it in a freezer-safe bag and pop it in the freezer. It’s best to use uncooked salmon within three months for best quality, and cooked salmon within six months. (Learn how to tell if freezer-burned food is safe to eat.) Another option is to make smoked salmon, which is good for one to two weeks in the refrigerator.

Also, find out how long asparagus lasts and how to tell if asparagus is bad.

Easy Salmon Recipes to Make for Dinner

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Grilled Salmon Fillet Exps Diyd21 14056 E05 12 10b

Grilled Salmon FilletHere's a prime example of salmon's ability to transform with strong flavors. A rich glaze of soy sauce, red wine vinegar and lemon soaks into the fish while fresh Parmesan crusts the outside.