How to Tell If Salmon Has Gone Bad

The Short Answer

Bad salmon smells sour, fishy, or ammonia-like instead of mild and ocean-fresh. The flesh feels slimy or tacky rather than firm and moist, and the color looks dull, grayish, or has milky patches. If any of those signs are present, throw it out. Fresh salmon should smell clean and look vibrant.

The stakes are higher with fish than with most other proteins. Spoiled salmon can carry bacteria that cause serious foodborne illness, so when in doubt, discard it.

How to Check Raw Salmon

Use your senses in this order — smell first, then look, then touch.

Smell: This is the most reliable indicator. Fresh salmon smells mild, slightly briny — like the ocean, not like fish. If it smells sour, pungently fishy, or has any hint of ammonia, it has turned. A strong fishy odor means bacterial breakdown is well underway.

Appearance: Fresh salmon is vibrant — bright pink to deep orange for most varieties, deep red for sockeye. Look for these warning signs:

• Dull, grayish, or faded color
• Milky white film or residue on the surface
• Dark spots that were not there before
• Flesh that looks dried out at the edges

The white lines running through salmon (fat lines) are normal. A milky coating on the surface is not.

Texture: Press the flesh gently with a finger. Fresh salmon is firm and springs back. If it feels mushy, slimy, or leaves a sticky residue on your finger, it is past its prime. A slight natural moisture is fine — a slippery, slick film is not.

How to Check Cooked Salmon

Cooked salmon is harder to evaluate because cooking changes the color and texture. Focus on smell and the timeline.

Smell: Cooked salmon that has gone bad smells sour or unpleasantly sharp. If you have to ask whether it smells off, treat that uncertainty as a yes.

Texture: Cooked salmon that has spoiled may feel slimy on the outside or unusually dry and crumbly. Neither is normal for properly stored leftovers.

Timeline: Cooked salmon lasts 3 to 4 days in the refrigerator when stored in a sealed container. If it has been longer than that, discard it regardless of how it looks or smells — some harmful bacteria do not produce obvious signs.

How Long Does Salmon Last?

• Fresh raw salmon: 1 to 2 days in the refrigerator from the date of purchase. If you will not cook it within that window, freeze it.
• Cooked salmon: 3 to 4 days in the refrigerator in a sealed container.
• Smoked salmon (unopened): Follow the date on the package. Once opened, use within 5 to 7 days.
• Frozen salmon: Safe indefinitely in the freezer, but quality is best within 2 to 3 months. Freezer burn does not make it unsafe, just dry and less flavorful.

These windows assume the salmon has been stored at 40 F or below the entire time. If it sat at room temperature for more than 2 hours — or more than 1 hour in temperatures above 90 F — discard it.

Common Questions

Is it normal for salmon to smell a little fishy? A faint sea-like smell is normal. A strong, sharp, or sour fishy smell is not. Think of the difference between a fresh ocean breeze and a fish market dumpster. You will know the difference.

What about the white stuff that comes out when you cook salmon? That is albumin — a protein that coagulates and rises to the surface during cooking. It is completely harmless and normal. It does not mean the salmon is bad.

Can I eat salmon past its sell-by date? The sell-by date is a store guideline. Use your senses. If the salmon smells fresh, looks vibrant, and feels firm within a day or two of that date, it is likely fine. More than 2 days past the sell-by date, err on the side of caution.

Quick Summary

• Fresh salmon smells mild and ocean-like, not fishy or sour
• The flesh should be vibrant in color — dull, gray, or milky means it is turning
• Firm and moist is good; slimy, sticky, or mushy is bad
• Raw salmon lasts 1 to 2 days in the fridge; cooked salmon lasts 3 to 4 days
• Freeze raw salmon if you will not cook it within 2 days
• When in doubt, throw it out — the risk is not worth it