Does Fish Sauce Go Bad? How Long Does Fish Sauce Last?

If you’ve ever eaten Vietnamese food or perused through an Asian supermarket, chances are you’ve come across fish sauce. Maybe you have a bottle at home and are unsure whether it’s still safe for consumption.

Quick Answer

Fish Sauce does lose its flavor and spoils over time, but its shelf life is significantly longer than other condiments and sauces. Unopened fish sauce has a shelf life of 3-5 years when kept out. Refrigeration will keep fish sauce fresh for 3 years after it’s been opened. Freezing is not advisable as your freezer is not cold enough to freeze fish sauce.


The shelf life of fish sauce depends predominantly on where it’s stored and whether it is sealed properly. If you’ve ever wondered how long fish sauce actually lasts, read on.

Does Fish Sauce Go Bad? How Long Does Fish Sauce Last?

Fish sauce is a tough sauce to spoil. Its tenacity is due to the amount of salt and oil present, making it an environment inhospitable to most pathogens and bacteria.

What Is A Fish Sauce’s Shelf Life?

Light and heat are enemies of fish sauce. If left out in the sun, fish sauces will spoil much faster as bacteria is more likely to grow at warmer temperatures.

Opened, exposed to heat and light: Fish sauces may only last 1 to 2 months if kept in close contact of light and heat.

Unopened, room temperature: If sealed and kept at room temperature, fish sauce will go the distance—3 to 4 years, even 5 years for some brands.

Opened, sealed properly, in cold & dark: Fish sauces can last 1 year without spoiling if kept in a cool, dry place.

How Long Does Fish Sauce Last In The Fridge?

Refrigerating fish sauce extends the life of the sauce upwards of 3 years. The cold temperature prevents bacterial growth and preserves the sauce even further. Due to the salt bounded with water molecules, fish sauce preserves very well and thus refrigerating isn’t necessary if stored properly. However, you can opt to store your sauce in the fridge for the long haul without any sacrifice in taste or quality.  Note that if you have homemade fish sauce, it must be stored in an airtight container to prevent spoiling.

How Long Does Fish Sauce Last In The Freezer?

Freezing fish sauce might add another two years, a total life upwards of 7 years. However, fish sauces cannot freeze in a standard home freezer, so it would be ill advised to store your fish sauce in the freezer. The same effect can be obtained by storing fish sauce in the refrigerator, so a freezer is not necessary.

When in doubt, check the ‘Best By’ dates on the bottle. They’re meant to tell when to consume for best quality. Anytime after that, the sauce may still be good, but not great.

How Can You Tell If Fish Sauce Is Still Good?

Appearance of Sauce: Take a look at the sauce’s color. If you think you’re seeing soy sauce, it’s because the sauce has begun to oxidize. Fresh fish sauce has a distinct amber, golden color. When sauces interact with air, oxidation takes place and the sauce darkens and becomes saltier. While this isn’t a deal breaker, it means the quality of its taste has begun its decline. Much like wine, fish sauce has its peak flavor and steady decline.

Check bottle for mold: Yeast can grow in the neck or inside the bottle. If there is mold growing anywhere in the bottle, the fish sauce has spoiled and should be thrown out.

Salt Crystals: Sometimes, salt crystals will harden and sink to the bottom of the bottle. This is normal and does not affect the taste of sauce.

Smell:  Fish sauce is essentially fermented fish. Therefore, a ‘fishy’ smell is normal when you use fresh sauce. If you smell something ‘off,’ chances are the fish sauce has expired.

Taste: The best way to check to see if fish sauce is still good is with a taste test. Fish sauce becomes saltier and darker with time. If the saltiness is unbearable, it may be time to buy a new bottle.

How Do You Store Fish Sauce?

In order to decide how you should store fish sauce, determine the frequency of your fish sauce usage.

Used frequently: If you love the taste of fish sauce and use it often, it’s best to keep bottles tightly sealed and stored in your cupboard.

Used sparingly: If you only use fish sauces on rare occasions and don’t need it on hand, it’s best to store in the fridge.

Remember that the best way to preserve fish sauce is to keep it away from heat and light. Also note when kept at room temperature, fish sauces will become gassy and release gasses when opened. If you don’t want this to happen, opt to keep the sauce in the fridge.

Should You Freeze Fish Sauce?

It is not recommended to freeze fish sauce. Fish Sauce contains salt, oil, and preservatives, all of which lower the fish sauce’s freezing point. When water freezes, water molecules bond with each other, slowing down and eventually standing in place. Salt and oils in fish sauce prevent the molecules from bonding. Even if you wanted to, your fridge wouldn’t be able to freeze the sauce. Most household refrigerators freeze aren’t cold enough to freeze fish sauces.

Wrap Up

If you take care of it, that bottle of fish sauce in your cupboard will outlast most of your other condiments and sauces. Do you have any ‘fishy’ questions about fish sauce? Has your sauce crossed the 5 year limit and still tastes good?  Share your questions and comments below!

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