Can You Put Plastic In The Dishwasher?

By Cory White
Can You Put Plastic In The Dishwasher?

Plastic has become an integral part of our daily lives, including our kitchenware. But when it comes to cleaning plastic items, particularly in the dishwasher, concerns, and questions like ‘Can you put plastic in the dishwasher?’ usually come up. 

To answer this question, yes, it is possible to put some types of plastic in the dishwasher, but not all. Always check whether your plastic utensils, dishes, or containers are labeled as dishwasher safe before popping them in for a wash.

In this article, I will discuss the compatibility of plastic with dishwashers, examine the potential risks, benefits, and precautions, and explore the impact of heat, detergents, and the different types of plastic. Let’s go!

Safety of Plastics in Dishwasher

plastics in dishwasher

When it comes to plastic safety in the dishwasher, your key consideration should revolve around the type of plastic and the heat exposure. Certain plastic items are designed to withstand high temperatures within dishwashers, but not all plastic items possess the same resilience to heat.

Dishwasher safe plastic

These items are indicated with a label or symbol and can withstand the heat within the dishwasher. They are also tested to ensure no harmful chemicals leak into your food.

High-temperature plastic

Items made from high-temperature plastics, such as melamine, can be placed in the dishwasher as they are resistant to heat.

Heat sensitive plastics

On the other hand, heat-sensitive plastics can warp, melt or release harmful chemicals when exposed to high temperatures in dishwashers.

Reusable Plastic Containers and Dishwashers

reusable plastic containers

Reusable plastic containers are commonplace in most kitchens, and yes, many of them can be cleaned in a dishwasher under the right conditions. However, we need to pay attention to a few factors before giving it a go.

  • Dishwasher-safe marking. Check your reusable plastic containers for a marking indicating that they’re dishwasher safe. This usually confirms that the container can handle the heat without warping or releasing harmful chemicals.
  • Placement in the dishwasher. Even with dishwasher-safe containers, placement is critical. Consider using the top rack, as it is typically subjected to lower temperatures than the bottom rack, thereby reducing the chance of any damage.
  • Lids and Covers. Many plastic container lids are not dishwasher safe. Unless otherwise stated, it’s best to hand wash these to preserve their integrity.
  • BPA-free plastics. These kinds of reusable plastic containers are generally safe for dishwashers. BPA-free plastics don’t release any potentially harmful substances when they come into contact with heat.

Plastic Tableware and Cutlery

plastic cutlery

When it comes to kitchen items and dishwashers, one group that often raises questions concerns plastic tableware and cutlery. While many of these items can be washed in dishwashers, not all are suited to it.

Plastic Cutlery

Many types of plastic cutlery are dishwasher safe, but often it’s recommended to place these on the top rack due to the lower heat exposure. However, always double-check the manufacturer’s instructions because some types can warp, melt or even crack from the high temperatures.

Plastic Dishes

Similar to cutlery, many plastic dishes might be labeled as dishwasher safe. Again, it’s better to stack them on the top rack to reduce the risk of damage. Thicker plastic dishes can generally withstand heat better than thinner ones.

Plastic Glasses

These can often be dishwasher safe, but due to their shape, they might not dry fully. So, it’s best to hand dry them after the dishwashing cycle to prevent water spots.

Disposable Plastics

single use plastic

Let’s segway into disposable plastics – those usually light, single-use items that are so convenient for picnics or parties. While they’re incredibly helpful at these events, it’s generally a no-go when it comes to washing them in a dishwasher.

  • One-time Use: Disposable plastics are primarily intended for one-time use. They are usually not made to withstand high temperatures and will likely warp or melt in a dishwasher.
  • Thin and Light: These items often warble and can be tossed around by the water jets inside the dishwasher, potentially blocking spray arms or even the drain.

In essence, while it might be tempting to try and get another use out of your disposable plastic paraphernalia by washing them, it is not recommended. The dishwasher’s high heat and vigorous water jets can damage these items, and in turn, possibly your dishwasher. It’s best to reduce, reuse (where appropriate, and not in a dishwasher), and recycle disposable plastics whenever possible.

Understanding BPA-free Plastic

bpa-free plastic

Now, let’s dive into understanding BPA-free plastic and what it means in the context of dishwasher safety. BPA, or Bisphenol A, is a chemical used in making certain types of plastic but has raised health concerns due to its potential effects when ingested.

  • Health Safety. BPA-free plastic is so named because it does not contain the potentially harmful chemical Bisphenol A, which makes it safe for food and drink storage.
  • Dishwasher Compatibility. Being BPA-free does not automatically mean that a plastic item is dishwasher safe. The suitability of a plastic item for a dishwasher depends mainly on the type of plastic and its heat resilience.
  • Label Verification. Always check the label on BPA-free plastics for an indication of whether they’re safe to clean in a dishwasher.

Dishwasher Symbols for Plastics

To aid in the understanding of dishwasher safety, manufacturers often use symbols on plastic items. Knowing what these dishwasher symbols mean can be extremely handy when deciding if a plastic item can be cleaned in a dishwasher.

Dishwasher Safe Symbol

The most common symbol signaling that a plastic item is a dishwasher safe resembles a square with plates or glasses inside. It may also include the words “dishwasher safe.”

Top Rack Symbol

Another symbol you might find looks similar to the dishwasher safe icon but includes a line indicating the top half of the dishwasher. This icon is used to indicate that the item should be placed on the top rack only.

Heat Setting Symbol

An icon displaying a heating element (found near the bottom of your dishwasher) with a line crossing it out, means that the plastic shouldn’t be exposed to intense heat, indicating a ‘cold wash only’ instruction.

Beware, though – symbols can vary among different brands, so always check the product documentation to be sure. Moreover, the absence of any symbol doesn’t necessarily imply that the item is not dishwasher safe- in such cases, it’s always safer to hand wash the item or check directly with the manufacturer.

The Don’ts of Dishwashing Plastics

different plastics

Now we’ve covered the dos, let’s delve into the don’ts of dishwashing plastics. There are indeed some plastic items and conditions that are not suited for cleaning in a dishwasher.

Untested Plastic Items

If a plastic item is not clearly labeled as dishwasher safe, it’s a good practice not to put it in the dishwasher. These items may not withstand the heat and could warp or leach chemicals. Remember, when in doubt, it never hurts to opt for hand washing. It’s always better to be protective of your plastic items and your dishwasher too!

Plastic Bags and Wraps 

Thin plastic items like grocery bags, cling film, and zip-lock bags should not be run through a dishwasher as they cannot stand the heat and can easily block the dishwasher parts.

Disposable Plastic

As tempting as it might be to try and get another use out of your disposable plastic wares by washing them, it’s not the right place to do it. They are not meant to withstand high temperatures and can warp or melt.

BPA-Free Plastic Without Clear Labels

While BPA-free plastic is safer for food storage, it doesn’t mean these items are always dishwasher-safe. Always check for a dishwasher-safe label.

Plastic Types and Dishwasher Safety

pp plastic symbol

Lastly, let’s unwrap the mystery around different types of plastics and their suitability for dishwasher cleaning. It’s key to remember that not all plastics are made equal when it comes to tolerating high heat and water pressure.

High-Density Polyethylene (HDPE)

This type of plastic, often used in milk jugs and plastic bags, tends to be dishwasher safe but always check the label for confirmation.

Polypropylene (PP)

Found in items like yogurt containers and bottle caps, polypropylene is generally dishwasher safe. Again, double-check for a dishwasher-safe label.

Polystyrene (PS)

This material, used in disposable cutlery and foam cups, is usually not dishwasher safe and can warp or melt under high heat.

Polycarbonate (PC) / Other (O)

These plastics often contain BPA, and while there may be BPA-free versions available, they may not be dishwasher-safe. Always treat these with caution and check for specific instructions.


In essence, while it’s certainly possible and convenient to put many types of plastic in the dishwasher, not all plastic is dishwasher safe. Remember to check for dishwasher-safe labels or symbols on your plastics, particularly those labeled as BPA-free, and always place dishwasher-safe items on the top rack whenever possible. Whether you’re washing reusable plastic containers, plastic tableware, and cutlery, or questioning if a certain plastic item is dishwasher friendly, a little bit of knowledge can make a sizeable difference in achieving the cleanliness you want and need.

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