How to Reheat Mashed Potatoes

Mashed potatoes are a very versatile dish for many types of meals. They make for a great appetizer, but often this fact will also leave you with leftovers.

Mashed potatoes can last for up to five days in the refrigerator, and they can certainly be reheated. But, just tossing them in an appliance and crossing your fingers will likely not yield sufficient results.

Mashed potatoes can be reheated in pretty much anything that heats food. There are often extra steps to take to ensure best results, and they must be stored properly.

Properly Storing Mashed Potatoes

Put your leftover mashed potatoes in an airtight container in the fridge as soon as possible. An airtight container will help to prevent the mashed potatoes from becoming contaminated. It will also ensure that they don’t dry out too much and help preserve their taste and texture.

A wide and shallow container is best for storing mashed potatoes, as it helps with the reheating process. It will help them cool evenly, and thus can ensure that they reheat evenly as well. Mashed potatoes will stay good in the fridge for around three to five days.

If you don’t think you will eat your leftovers within a few days, mashed potatoes can also be kept in the freezer. Before freezing mashed potatoes, they need to be at room temperature. When freezing mashed potatoes, keep them in freezer bags. They can stay good for as long as a year when frozen properly.

Reheating Mashed Potatoes

There are various methods to reheat mashed potatoes. The main thing you want to avoid when reheating them is letting them dry out. They are difficult enough to cook in the first place, so it’s understandable that they are delicate to reheat. But there are a few foolproof ways to do so.

Technically, mashed potatoes can be reheated as many times as you want, as long as you’re reaching a safe internal temperature each time. But the quality of them will lessen each time, and it is not advisable to reheat them more than three or four times because of this.

Reheating Mashed Potatoes in Oven

Using an oven to reheat your leftover mashed potatoes is one of the best methods. This is because it gives you the most control over the process, as the oven is also the slowest way to reheat leftovers. You’ll want to add some extra liquid and oil, and cover them to help trap in moisture. Here are the steps to take to properly reheat mashed potatoes in the oven:

  1. Grab a dish that is oven-safe and place the mashed potatoes in your dish.
  2. Melt some butter and stir it into the potatoes. The result should be noticeably different but not runny. Instead of butter, you could also use broth, oil and cream, or milk.
  3. Next, cover the oven-safe dish with a corresponding lid or aluminum foil. Preheat the oven to 350 degrees Fahrenheit.
  4. Cook for 20 to 30 minutes, until the mashed potatoes are thoroughly heated. The internal temperature should be at least 165 degrees Fahrenheit.

Reheat Mashed Potatoes in a Slow Cooker

Using a slow cooker is another great contender for reheating mashed potatoes. Again, this is due to the slower process that leaves you with more control over the results. It does take some patience but on the bright side, they are very unlikely to dry out this way.

  1. First, line the slow cooker with butter or oil. Add a splash of liquid to the bottom of the pot as well.
  2. Stir your preferred liquid into the mashed potatoes before putting them in the pot. Like with the oven, they should not be runny, but silky.
  3. Add the potatoes and cover them. Cook on a low setting, until they are heated through. It should take about four hours. Check periodically to see if they are thoroughly heated.

A slow cooker by far takes the longest to reheat mashed potatoes. But it’s great if you’re making them to serve along with a large meal that requires a lot of preparation. It allows you to use the oven for other foods at the same time.

Reheating Mashed Potatoes in Microwave

Using a microwave to reheat mashed potatoes is definitely the fastest way. Because of this, though, it also runs the highest risk of drying out the potatoes. You don’t want too much moisture, but you don’t want too little. So using a microwave is tricky, but possible.

To reheat mashed potatoes in the microwave, first place them in a microwave-safe bowl. Then stir in some melted butter, or one of the alternatives listed above. Cover the bowl and set the microwave to 50% power, and heat for one minute.

After the initial heating, stir the potatoes and heat again for one minute. Continue this process until they are evenly heated. If they seem to be getting too dry, stir in more liquids. If they look too slimy, turn the power down.

Best Way to Reheat Mashed Potatoes

The best way to reheat mashed potatoes is by far the oven. It is a happy medium between using a microwave and a slow cooker, and gives you just enough control over the end result. If done properly, they shouldn’t be too dry or too runny. 

While it does take some more planning and time than using a microwave, it is much more likely to give you the results you’re looking for.

How to Reheat Instant Mashed Potatoes

Instant mashed potatoes can also be reheated. They are best kept in the freezer, though, even if you are planning on eating them within a couple of days. Instant mashed potatoes can be reheated in the same way that regular mashed potatoes can.

They dry out much easier, so it’s important to check on them regularly and heat on a lower setting, for less time. For example, if using a microwave, follow the exact same instructions, but heat in thirty second intervals instead of one minute ones.


There are multiple ways to safely reheat mashed potatoes and still have a tasty result. The key is to make sure they don’t get too dry or too runny. This is certainly an achievable task, and the best way to reheat mashed potatoes is in the oven as it will give you the most control over how the end result turns out.