Does Mayonnaise Need To Be Refrigerated? + Other Related FAQs

Many popular condiments like ketchup and soy sauce can last for a long time, but how long these condiments can last often depends on whether they are refrigerated or not.

You may be wondering if you need to refrigerate your mayonnaise. I did some research, and here is what I discovered!

Does Mayonnaise Need To Be Refrigerated?

Ideally, mayonnaise needs to be refrigerated after opening to keep the mayonnaise at peak quality for a longer time. Typically, opened mayonnaise kept out of the fridge will only last for 8 hours, but unopened mayonnaise can stay unrefrigerated for a longer time. Moreover, foods with mayonnaise should be kept refrigerated.

Do you want to learn more about why mayonnaise has to be refrigerated? Check out the rest of the article to find out!

Does Mayonnaise Spoil If Not Refrigerated?

Mayonnaise is a perishable product since mayonnaise contains eggs, meaning mayonnaise can spoil especially when the mayonnaise is not refrigerated.

However, how quick mayonnaise spoils will highly depend on the brand, storage, and if you opened the mayonnaise.

How Long Does Unopened Mayonnaise Last Unrefrigerated?

While it will depend on the brand, most unopened mayonnaise can last unrefrigerated for 1-2 years given that the mayonnaise is kept in a dark and cool place.

Moreover, you can refer to the mayonnaise label since most manufacturers will put a best-by or expiration date.

How Long Can Opened Mayonnaise Stay Out Unrefrigerated?

Most unopened mayonnaises will only last for eight hours unrefrigerated because the mayonnaise will spoil quickly at room temperature once exposed to air.

Even if you close the jar of mayonnaise after opening, the mayonnaise has been “contaminated” and will go bad at warmer temperatures, which is why opened mayonnaise should stay in the fridge.

Do You Have To Refrigerate Mayonnaise After Opening?

You need to refrigerate your mayonnaise once you open it to prevent quick spoiling and to keep the mayonnaise at peak quality for a longer time.

While certain mayonnaise brands state that refrigerating mayonnaise is to keep the best flavor rather than preventing the mayonnaise from spoiling, mayonnaise generally goes bad at room temperature once opened.

Moreover, warmer temperatures can cause the mayonnaise to split and change color, meaning unrefrigerated and opened mayonnaise cannot be used even if the mayonnaise did not spoil.

How Long Can A Sandwich With Mayonnaise Stay Out?

How Long Can A Sandwich With Mayonnaise Stay Out?

Normally, sandwiches with mayonnaise can stay out of the refrigerator for up to four hours before the mayonnaise begins to spoil.

However, it is important to note that other ingredients in the sandwich, like meat and veggies, could spoil quicker than mayonnaise.

Therefore, if other ingredients have gone rancid in your sandwich, you cannot eat the sandwich even if the mayonnaise is still fresh.

How Do You Know When Mayonnaise Goes Bad?

One way to know if mayonnaise has gone bad is by opening the mayonnaise and smelling the mayonnaise, and the mayonnaise has gone bad if there is a putrid or rancid smell.

Another method to check if mayonnaise has spoiled is by looking for mold, particularly at the neck of the mayonnaise’s jar.

If the mayonnaise has split, the mayonnaise may still be okay to eat but the mayonnaise will be difficult to use and taste odd.

How Long Can Mayonnaise Sit Out In The Sun?

Since mayonnaise can only stay fresh when kept out of the sunlight, mayonnaise can only sit out in the sun for up to two hours before the mayonnaise starts to spoil.

However, the mayonnaise can go bad faster if the temperatures are very hot, especially if the mayonnaise is under direct sunlight.

Can You Freeze Mayonnaise?

Technically, you can freeze mayonnaise but you will not get the same use out of your mayonnaise once thawed.

Frozen mayonnaise will look normal, but the emulsification of the mayonnaise will break when thawed, meaning you will lose the mayonnaise’s consistency.

Why Do Some Mayonnaises Not Need To Be Refrigerated?

Some store-bought mayonnaise brands contain a lot of acids like vinegar and lemon juice, which can extend the shelf-life of many food products.

However, mayonnaise still contains eggs that will eventually go bad, especially once exposed to air.

Therefore, mayonnaise should still be refrigerated once opened to prevent the eggs from spoiling quickly.

Take a look at our other articles to find out if mayonnaise expires, what mayonnaise tastes like, and what the difference between mayonnaise and Miracle Whip is.


Generally, it is ideal to refrigerate mayonnaise after you open the mayonnaise, but unopened mayonnaise can be kept out of the fridge for up to 1-2 years.

While certain brands state that refrigerating mayonnaise keeps the quality rather than preventing spoilage, it is always ideal to refrigerate mayonnaise once opened.

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