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

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

Even though fish sauce is a long-lasting condiment, it still has an expiration. So if you’re wondering if fish sauce goes bad, here’s our best FAQ!

Fish sauce is a liquid amber-colored condiment made of anchovies coated in salt and fermented for a couple of months to years. 

It plays the role of driving the flavor of most Southeast Asian cuisine, making it a staple ingredient in the region. 

It is also a perfect addition to any dish, not just the Asian ones. 

You will enjoy the flavor of fish sauce (also called nuoc mam in Vietnamese) because of its earthy, savory flavor that makes foods like mushrooms, roasted tomatoes, and soy sauce rich in taste and crave-worthy. 

On the other hand, fish sauce is rich in umami, known as the fifth taste and commonly found in animal proteins. 

Umami is a Japanese term that means “pleasant savory taste.”

Some chefs use fish sauce to balance out the bitter taste of the vegetables. 

Sure, there’s a strong, pungent fishiness to the sauce, but it is balanced with a salty, briny, caramel-y sweetness.

Now, we know for a fact that its fermentation takes months and years, but how about its shelf-life and does fish sauce go bad

Read along to learn about this popular flavor enhancer in the Asian market. 

You may notice the same old fish sauce bottle among the condiments in your mom’s kitchen cabinet or fridge. 

And you’ll start to wonder if this half-full bottle of fish sauce ever goes bad. 

Really, does fish sauce go bad?

The answer is yes. 

Although it has plenty of salt that acts as a preservative and allows it to last for years and delay spoilage, it gets bad eventually. 

And once it goes bad or way past its expiration date, it will lose its flavor over time. 

Tip: you can keep it for a year after its best-by date. 

An unopened fish sauce can be kept for two to three years. 

While the opened fish sauce will take three to six months at room temperature and a year if kept inside a refrigerator. 

But worry not because there are indicators that will tell you if the fish sauce is spoiled or not.

How to tell if fish sauce has gone bad?

Truth be told, it is difficult to determine whether or not fish sauce has gone bad. 

This is because there are a few instances in which some people believe that it is spoiled when in fact, it is not.

One of those occurrences is the presence of clear crystal on top of the bottle’s neck. 

Those crystals are made of sea salt, and the procedure by which they were formed is entirely natural.

It has no effect on the quality of the condiment.

Secondly, the particles floating in the sauce are not indicative of deterioration.

These are proteins generated as a result of the protein precipitation process.

It is also a natural process that occurs when a condiment is exposed to changes in temperature.

In addition to that, it is safe to consume and does not affect in any way the flavor of the sauce. 

Meanwhile, let’s look at the signs that your fish sauce has gone bad.

  • Toss the bottle as soon as possible if you see any symptoms of mold or yeast on the bottle’s surface.
  • If your fish sauce has an unpleasant or putrid scent, this is a sign that it has already gone bad.
  • You need to throw away your fish sauce if it tastes strange or if it has a different flavor than usual.

You must pay close attention to the flavor of the fish sauce.

If it has a sour or bitter flavor, then it has gone bad and needs to be thrown away.

How long does fish sauce last?

Fish sauce can indeed go bad, but this process takes a very long time if it is properly stored.

It is known to retain its quality when kept at room temperature for an extended amount of time.

On the other hand, if it is left unopened and is then exposed to sources of heat or light, it will spoil in a few days.

Almost every bottle of fish sauce has an expiration date indicating an estimate on how long the fish sauce will remain flavorful and fresh.

Although there is no legal requirement in the United States for fish sauce bottles to bear an expiration date, most manufacturers opt to indicate dates on the label anyway. 

That is to harbor trust from the consumers who prefer to rely on the products with a use-by label. 

However, due to the high salt content of fish sauce and the absence of any other components that might cause it to spoil, it has a shelf life that extends much beyond its expiration date.

And it could take months to years. 

If you keep it for a long period, the quality will deteriorate until it loses its taste and takes on a milder flavor.

A bottle of fish sauce can maintain its quality for an additional year after the date it was initially supposed to expire as long as it has not been opened.

When stored in the pantry, an opened bottle has the potential to stay fresh for up to six months, while keeping it in the refrigerator can extend its shelf life to more than a year.

Does fish sauce need to be refrigerated?

It is entirely up to you whether or not to keep the fish sauce in the refrigerator.

Either doing so or deciding to keep them on a shelf in your pantry is a good choice; there is no wrong answer here.

Because there is no requirement that fish sauce should be kept in the refrigerator in the first place. 

It will be alright as long as it is maintained in a cool, dry environment, away from direct heat or sunlight. 

However, some people refrigerate their fish sauce to make it last for a longer period, where it maintains its umami flavor while also retaining its best quality.

Yet, one brand of fish sauce requires the bottle to be refrigerated, which is the Red Boat Fish Sauce.

How long will fish sauce last after it is opened?

When stored at room temperature, an opened bottle of fish sauce will keep its optimal quality for three to six months if tightly sealed.

The flavor of the fish sauce may be less pungent, less pleasant, or less fresh-tasting after the said period. 

Meanwhile, if you do not use fish sauce regularly, you may store it in the refrigerator once it has been opened and let it sit there for up to one year. 

And its freshness may be maintained for a significantly more extended period.

How long does fish sauce last in the fridge?

In general, condiments are considered to be pantry staples. 

They may sit on the shelf for long periods and do not require refrigeration.

Like fish sauce which has gone through a lengthy fermentation and production process. 

Hence, it is safe to keep it at room temperature.

However, a period of time spent in freezing temperatures can help extend its shelf-life by several months to a year. 

So if you want to extend its shelf life, store it in a refrigerator rather than in the pantry. 

On the other hand, when a bottle of fish sauce is opened, the average shelf life is drastically shortened to a maximum of six months at room temperature. 

And will retain its flavor even after being refrigerated for up to a year.

But an unopened bottle of fish sauce has a shelf life of up to three years. (Red Boat FAQ)

Lastly, pay attention to the expiration date printed on the packaging seal, even if the item has been stored in the refrigerator.

Tips on storing fish sauce

Fish sauce rarely spoils, but its quality may decline over time if not preserved appropriately.

So here are some reliable tips on storing fish sauce:

  1. Always keep the bottle tightly closed after opening it.
  2. The quality of the fish sauce might be negatively impacted by exposure to sources of light and heat.
  3. This condiment will not spoil if left at room temperature for a week to months because of the high salt content.
  4. If you plan to keep it for a long time, putting it in the refrigerator is a good idea to keep its best quality for as long as possible.
  5. If you want to keep the fish sauce in the freezer, you should place it in a container with a secured lid.
  6. Putting it in a sealed bag will make it impossible to tell if the fish sauce has gone bad.
  7. Although it is permissible to use fish sauce past its expiration date, be mindful of its odor, color, and taste before adding to the rest of your recipe ingredients.

CookingChew Tip: If the smell or taste is questionable, and the bottle has a long-past freshness date, here are some of our ideas for fish sauce substitutes.

The bottom line

Fish sauce is a fantastic ingredient if you want to spice up your dish.

It adds the appropriate flavor and amplifies savory undertones in your cuisine, making it mouth-watering and delightful.

In all honesty, fish sauce makes a great addition to the perfection of any dish.

So, if it’s allowed, try it in your recipe and see how it lifts and elevates the tastes of your cuisine.

Does Fish Sauce Go Bad? 🤔 Storage Tip

Does Fish Sauce Go Bad? 🤔 Storage Tip

Even though the fish sauce is a long-lasting condiment, it still has an expiration. So if you’re wondering if fish sauce goes bad, here's our best FAQ.


  • Fish sauce
  • Airtight container
  • Pantry


  1. Put fish sauce in an airtight or its original container. 
  2. Store fish sauce on the shelf in your pantry, preferably away from sunlight.

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