Let’s talk about keeping the best side dish ever crisp, fresh, and safe to eat.

There’s nothing better than a hearty, comforting bowl of potato salad when you and your family are hungry.

Just boil the potatoes, dress them with mayo and vinegar, season them with salt and pepper, and then toss them with green onions—and you have yourself a meal that’s so easy to prepare and so delicious that the spouse and kids will be wiggling their feed under the table in delight.

But how long does potato salad keep? And what’s the best way to store it?

That’s the part no cookbook author seems to address, and the one we’re here to help you find out.

Potato salad will keep 1-2 hours at room temperature and 3-4 days in the fridge (USDA). For food safety reasons, you should refrigerate the leftovers quickly and use them up within a few days of preparation.

In this post, we will discuss why potato salad shouldn’t be kept outside of the fridge and how to store it to keep it fresh and edible. We will also go into the best ways to tell if potato salad is spoiled and to dispose of it when it happens.

Why Can’t Potato Salad Sit Out?

Bacteria are a fact of life, and they are found all around us: in the air, in our water, and also in our food.

Our bodies are well equipped to fight off most species of bacteria that live on our food, but only up to a point. The more of them we ingest, the greater the risk of foodborne illness.

The trick to keeping cooked food safe is not to let it sit too long, whether on the countertop or on the dining table. Hot foods should be kept hot (above 140°F) and cold foods should be kept cold (below 40°F); the temperatures in between are dangerous.

Food safety experts call the temperature range from 40°F (4°C) to 140°F (60°C) the danger zone, and for good reason.

When you leave potato salad to sit out, the number of harmful bacteria on it doubles every 20 minutes. A few dozen germs can multiply to hundreds or even thousands within hours and cause food poisoning if you—or others in your household—eat them.

How to Store Potato Salad

This has several important implications for how you should prepare and serve your food.

Warm potato salad should be refrigerated within 2 hours of preparation. On hot summer days, when the outside temperature is 90°F (32°C) and above, this time is reduced to 1 hour.

Cold potato salad, especially if made with mayo or cream, should be kept in the fridge. If you’re serving the salad from a bowl, take it out of the fridge, plate it, and then put it back in. (You can take it out again at any time for top-ups.)

If a bowl or individual plates of potato salad has sat on the countertop or dining table for more than 1-2 hours, you have no way to check if it’s still safe to eat or not. To put it simply, if you’ve kept potato salad at room temperature for more than 1-2 hours on the table or more than 3-4 days in the fridge, you should throw it away.

Not everyone knows that the pathogenic bacteria that cause foodborne illnesses are not the same species of bacteria that cause spoilage in food. It’s easy to tell if your potato salad has spoiled because it will smell disgusting. But it can be overgrown with pathogens, and yet smell and taste perfectly fine.

How to Tell If Potato Salad Has Gone Bad

Even if you follow the food safety basics we just covered down to the letter, your potato salad will eventually spoil. When in doubt, rely on your sense of sight, smell, and touch—but don’t taste it.

Spoiled potato salad will have a sour smell, and not in a good way. If it contains mayonnaise, the mayonnaise will have turned dark yellow and taken on a foul, putrid odor. Fuzzy organics like green or blue mold growing in spots are a tell-tale sign that the salad is no longer edible and should be discarded.

Some people mistakenly believe that they can make spoiled food edible again by heating it. This is a dangerous misconception that can make you and those around you sick.

It’s true that heat kills the disease-causing bacteria in your food. However, it doesn’t inactivate the poisonous heat-resistant toxins that these bacteria secreted while they were alive.

In other words, you can’t make spoiled potato salad safe again by heating or even cooking it; throw it away.

Disposing of Spoiled Potato Salad

Wondering about the best way to dispose of spoiled potato salad? We have everything for you, so read on.

Potato salad can go in the compost provided it doesn’t contain eggs or mayonnaise, as these two ingredients can attract critters and worms.

In some municipalities, residents are provided with a green organics cart that can be used to dispose of food and garden waste. These carts are collected on regular trash collection days and provide an environmentally friendly way to dispose of organics.

Generally, potato salad can go in the green organics cart, no matter if it contains eggs and dairy products or not. (Plastic containers and cans for the ingredients that went into the salad belong elsewhere.)

Of course, if you don’t have a compost pile or a green organics cart for your house or apartment building, you can always wrap the potato salad tightly in biodegradable garbage bags and throw it in the trash can.