LG washing machine Prewash Cycle: What Is It & How it Works

The prewash feature in an LG washing machine refers to an initial wash cycle that is used to remove heavy dirt and stains from clothing before the main wash cycle begins. During the prewash cycle, the machine fills with water and agitates the clothes with detergent for a brief period before draining the dirty water and proceeding to the main wash cycle.

So, this specific function soaks and tumbles dirty laundry in cool water mixed with detergent for a specific period of time.

The main purpose of the prewash cycle is to loosen and remove any stubborn stains or dirt that might not come out during the regular wash cycle.

Note: Most washing machines with pre-wash functions have a built-in small compartment to add detergent or a suitable cleaning solution.

Key Takeaways

  • The pre-wash function is simply a gentle tumbling cycle that runs before the main wash cycle.
  • It gently agitates the clothes by mixing detergent and water so that stubborn stains are either loosened or removed before the main wash cycle begins.
  • A pre-wash function is available to be merged or included with some of the available wash programs. So, as soon as the prewash cycle is complete it automatically transitions to the next cycle that you have selected.
  • Refer to the user manual of your washing machine to ensure that it includes a Pre-wash function and how to use it. Additionally, you will also be able to determine the compatible cycles that can include the pre-wash function.
  • Not all LG washing machines will have the Pre-wash function.
  • Read the care label on your clothes as well as the washing machine user manual to ensure that you are prewashing the right type of clothes.

Understanding the LG Prewash Cycle

The LG prewash cycle is a technology that is designed to help you achieve cleaner and fresher clothes without the need for traditional prewashing methods.

The prewash cycle is designed to remove tough stains and dirt from your clothes before the main wash cycle begins, thereby reducing the need for multiple wash cycles and saving you time and money.

Almost all leading washing machine brands like Whirlpool, GE, Maytag, Kenmore, Bosch, Samsung, LG, etc. have the prewash feature available in mid and high-range models.

It’s important to note that the term prewash cycle is also known as pre-treat, stain removal cycle, presoak cycle, or stain assist in some other brands and models.

Regardless of the terminology, the purpose remains the same i.e., to provide an additional treatment phase aimed at tackling stains and soiling before the main washing process.

How does the prewash cycle in the LG washing machine work?

prewash cycle workflow

The pre-wash cycle in an LG washing machine is engineered to pre-treat heavily soiled clothes before the main wash.

This cycle combines water and detergent to create a solution that penetrates the fabric fibers, effectively breaking down the dirt and grime.

The agitation of the washer further aids in loosening the stains, and preparing the clothes for thorough cleaning in the subsequent phases of the washing process.

Once the pre-wash cycle is selected along with a standard wash program, the washer will fill with cool water and dispense the detergent automatically.

The clothes are then soaked for some time and then agitated or tumbled inside the washtub.

However, a gentle spin is also offered to ensure the soapy water penetrates deep into the fibers in an even manner.

Finally, the used water is drained from the washtub, and the subsequent wash cycle is initiated accordingly.

Why use the prewash cycle?

Utilizing the pre-wash cycle is advantageous for garments that are dirty, filthy, grimy, grubby, or stained.

This cycle is particularly beneficial to prewash heavily soiled clothes and prewash tough stains, as it provides an additional layer of treatment, enhancing the ability of the LG washing machine to achieve cleaner and fresher laundry results.

The prewash cycle helps to loosen the tough stains and eliminate the lighter ones that would otherwise be difficult to remove through a conventional washing process.

Opting for a prewash cycle ensures a comprehensive cleaning.

In other words, it helps you get the most out of your LG washer.

Here are some of the benefits of using the LG Prewash Cycle:

Removes tough stains

The prewash cycle is specifically designed to target tough stains, such as grass and grease stains.

By prewashing your clothes, you can ensure that these stains are removed before the main wash cycle.

Saves time and energy

If you have to wash your clothes multiple times to get them clean, you’re wasting both time and energy.

By using the prewash cycle, you can reduce the need for multiple washes, which can save you time and energy in the long run.

Protects your clothes

Prewashing your clothes can help protect them from damage.

By removing dirt and stains before the main wash cycle, you can prevent these substances from being ground into the fabric, which can cause wear and tear over time.


The prewash cycle is easy to use and can be easily integrated into your regular laundry routine.

Also, there is no special prep work needed to use this cycle.

Just put the soiled garments into the washtub, followed by adding an appropriate amount of detergent and selecting the pre-wash option.

The washer should automatically handle the prewash cycle and proceed to the next cycle if it’s an automatic model.

How long does prewash cycle last in LG washing machine?

The prewash cycle typically lasts anywhere from a few minutes to around 30 minutes, ensuring ample time for the detergent to penetrate the fabric fibers and loosen the stains.

However, the duration of the pre-wash cycle in LG washing machines can vary depending on the model and the selected pre-wash settings on the LG washing machine.

Disadvantages of the Prewash cycle


The prewash cycle adds extra time to the overall washing process, which can be inconvenient if you’re in a hurry.

Water and energy usage

Running an additional cycle uses more water and energy, which can lead to higher utility bills and a less eco-friendly washing routine.

Wear and tear

Running more cycles can put extra wear and tear on your washing machine, potentially reducing its lifespan.

Detergent usage

Using more detergent during the prewash cycle can lead to extra detergent buildup in your clothes and washing machine over time.

Added Cost

Some washing machines may require the use of specific detergents or prewash additives, which can add to the overall cost of washing your clothes.

How to Use the LG Prewash Cycle?

Using the LG prewash cycle is a straightforward process. Start by selecting the Pre-wash+ Normal cycle on your LG washing machine followed by loading clothes and adding the correct type of prewash detergent, typically powder used in the main wash compartment.

Then, initiate the cycle, allowing the machine to pre-treat heavily soiled clothes and tough stains.

Upon completion, unload the laundry and continue with your usual drying process.

Let’s take a quick look at the step-by-step process in detail.

Step 1: Sort your clothes

Start by sorting your clothes based on their color and fabric type.

This will ensure that you don’t accidentally mix colors or damage delicate fabrics.

Step 2: Load your washing machine

Once you are done sorting your clothes based on color and type of fabric, simply put them in your LG washing machine.

Step 3: Add detergent

Now add your preferred detergent to the machine’s prewash detergent dispenser.

You can use the same detergent for both the prewash and main wash cycles.

Step 4: Select the prewash cycle

Look for the prewash plus normal cycle option on your washing machine’s control panel.

This cycle includes a built-in pre-wash function designed to treat stains and heavily soiled items.

Step 5: Start the cycle

Now press the start button to begin the prewash cycle.

Once you start the cycle, the machine will fill with water and begin agitating your clothes to remove any dirt or stains.

Note: If your washer is a fully automatic model, it will automatically proceed to the next cycle, and if it’s a semi-automatic model, you will need to manually select the cycle (refer to the user manual to go through these hidden features).

When should you use pre-wash in a washing machine?

The pre-wash function can be selected with your regular wash cycle to clean heavily soiled and stained items.

Additionally, you can select pre-wash to eliminate the need for handwashing heavily soiled items before washing them in the machine.

You can add your regular detergent or a stain pre-treatment solution into the machine during the pre-wash function.

The whole idea behind using a pre-wash cycle is to enable the washing machine to penetrate the fabric fibers more effectively, thereby breaking down the dirt and grime and ensuring a higher level of cleanliness.

Can you select pre-wash with any available cycle?

No, the pre-wash cycle cannot be selected with all the available wash programs and will vary depending on the cycle selected.

Most washing machines won’t allow you to select a pre-wash cycle with some wash programs. It is usually not available with delicates, quick wash, wool, rinse & spin, etc.

To select pre-wash you will first need to select your regular or desired cycle, and then you will be able to include pre-wash (check the user manual for more clarity on this).

If the pre-wash is not applicable for a particular cycle, then the pre-wash option will be either grayed out or will not allow you to include it with them.

Where should you add a detergent for the pre-wash function?

Most washing machines have a dedicated built-in compartment for pre-wash functions where you can add cleaning solutions.

However, you can also add detergent directly to the washtub.

If your washing machine model includes a separate compartment for pre-wash, make sure to add the detergent to both the pre-wash and main detergent compartments.

If you miss adding detergent to the main wash compartment, the following cycle will run without detergent being dispensed, resulting in unclean laundry.

How much detergent should you add for pre-wash?

As a general rule of thumb, adding only half the quantity of detergent to the pre-wash compartment should do the trick.

For example, if a load of laundry needs 2 cups of detergent in the main wash, then simply add 1 cup of detergent to the pre-wash compartment.

That being said, the quantity remains the same for the main detergent compartment.

Can you add baking soda for the pre-wash cycle?

Yes, you can add baking soda powder to the washtub for the pre-wash cycle.

The natural properties of baking soda will help loosen the dirt and stain particles and make it easier to clean the clothing in the following wash cycle.

However, it’s important that you check the care label of your clothes before applying this method.

Some fabrics may not be suitable for baking soda treatment, and it could cause damage or discoloration.

So, it’s always better to test a small, inconspicuous area first before applying it to the entire garment.

Alternatives to prewash

If your washing machine does not have a pre-wash function, you can use a few alternatives.

Use the Pre-soak or Soak function

For heavily soiled items, you can select the presoak or soak function if applicable in your washing machine model.

In some washer models, the pre-soak function allows you to soak heavily soiled garments before the actual wash cycle begins.

However, you can choose a desired duration at your convenience or depending on the soil level of the items.

In pre-soak, the garments are soaked in cool water mixed with detergent or pre-treating solutions.

Heavy-Duty cycles

If you simply want to figure out options for cleaning heavily soiled garments, there are other options available, such as a heavy-duty cycle.

This particular cycle is ideal for highly soiled and stained garments, however, make sure to refer to the care label of your garments before using this cycle.

This is because, in some cases, it may use hot water settings to clean dirty laundry.

Manual soaking or pretreatment

Another option is to soak the heavily soiled garments in a sink filled with water and detergent for a couple of hours.

Make sure to agitate the clothing with your hands at regular intervals.

Additionally, the garments should be submerged completely in the solution for best results.

Once done, discharge the used water and fill the sink with clean water again to rinse the garments thoroughly.

Finally, add them to the washing machine and run the desired wash cycle.

Troubleshooting minor issues with the pre-wash cycle in LG washing machines can be straightforward with the right approach.

Here are a few common problems and their solutions to ensure the smooth operation of your pre-wash feature.

Cycle Doesn’t Start

If the pre-wash cycle doesn’t initiate, double-check that you’ve accurately selected the prewash settings on the LG washing machine and confirm that the machine’s door is securely closed.

A loose door can prevent the cycle from starting.

Detergent Dispensing Issues

Encountering problems with detergent dispensing? Ensure that the LG prewash detergent is correctly placed in the designated compartment and that it isn’t clumped or past its expiration date.

Using the right type and amount of detergent is crucial for the effectiveness of the pre-wash.

Utilizing SmartDiagnosis System

LG’s SmartDiagnosis system is a valuable tool for identifying and resolving common issues.

By consulting this feature, you can receive real-time solutions and guidance on addressing minor problems related to the pre-wash cycle.

Regular Maintenance and User Manual Reference

Preventive measures such as regular maintenance of the washer and referring to the user manual for specific instructions and troubleshooting tips can significantly aid in avoiding and resolving minor issues, ensuring the optimal performance of the pre-wash function.

Final Thoughts

The pre-wash function in washing machines is designed to help remove stubborn dirt and stains from clothes before the actual washing cycle begins.

So, this feature involves agitating the fabric with a mixture of water and detergent in the machine’s drum before the regular cycle begins, thus helping to loosen any dirt or soiling.

The pre-wash cycle typically uses cold water and lightly spins to agitate the solution and help it work deeper into the fabric, but it can also use hot water in some models by setting the temperature appropriately for extra cleaning power.

Frequently Asked Questions

Do all washing machines have a pre-wash function?

The inclusion of a pre-wash function in washing machines is not universal, which means not all washing machine models will have this option. That being said, many modern-day washing machines offer the prewash option for a decent price; just check the user manual or check with the salesperson if you are specific about this feature.

Can I skip the prewash cycle?

While it’s not necessary to use the prewash cycle for every wash, it can be beneficial for clothes with tough stains or heavy dirt. If your clothes don’t have any noticeable stains or dirt, you may skip the prewash cycle.

Will the prewash cycle add extra time to my laundry routine?

Yes, since the prewash cycle involves soaking and gently agitating the clothes followed by flushing the water and refilling, it will add extra time to your laundry routine. However, it can save time in the long run by reducing the need for multiple washes.

Do I need to use a different detergent for the prewash cycle?

No, you can use the same detergent for both the prewash and main wash cycles. That being said, if you’re dealing with heavily soiled clothes, you may want to consider using a detergent that is specifically designed for tough stains.

How can I tell if my clothes need the prewash cycle?

If your clothes have visible stains or dirt, they may benefit from the prewash cycle. Additionally, if you’re washing heavily soiled items like work clothes or athletic gear, the prewash cycle can help to remove sweat, dirt, and other substances that can be difficult to clean with a regular wash cycle.

Manish Singh is an expert in electrical engineering with a Diploma in the field. With over 12 years of experience, he specializes in repairing music systems, washing machines, dryers, and other laundry-related appliances. His in-depth knowledge in electrical repairs and decent knowledge about garment care makes him a trusted authority in the field of appliance repair and laundry related topics. If you have any questions or need assistance with your appliances, you can reach out to Manish through email: manish.singh (at) portablelaundry.com