What Are Faucet Aerators and Why Should You Install Them?

Silver faucet with a flow of running water and exposed aerator

The Spruce / Sarah Lee

If you have ever unscrewed the end of a kitchen or bathroom faucet or felt inside with your finger, you may have discovered a device with a small metal screen disk—a faucet aerator. The aerator is an important feature that both improves the physical operation of the faucet and enhances the experience of using the faucet. Find out why the faucet aerator is sometimes misunderstood as being primarily a filtration device. Also, learn the aerator's many other valuable purposes and why you definitely want to have one on your faucet.

What Is a Faucet Aerator?

A faucet aerator is a small, round device that you can screw onto the tip of your faucet to create a more consistent, splash-free steam of water. Aerators usually create aa mixture of water and air, making the stream smoother. Generally, a standard faucet aerator will limit the water flow to 1.8 or 2.2 GPM (gallons per minute). This can vary & is less in some municipalities; for example, NYC is 1.5 GPM.

The dual-threaded collar allows the faucet aerator to be threaded counterclockwise onto the faucet.

Optionally, a plastic or metal disk with a hole in the center may be included as a flow restrictor. With the flow restrictor installed, you can expect the flow to drop to a water-saving 1.5 GPM. Some ultra water-saving restrictors will even bring the flow down to 0.5 GPM.

As the faucet aerator usually comes assembled, it only needs to be screwed onto the end of a faucet. The faucet must be displaying female threads since most aerators are male-threaded (exposed threads).

Faucet aerators first entered homes in the late 1940s as add-on devices that would reduce splashing and help water taste better by introducing oxygen. Today, faucet aerators are standard components on nearly all kitchen and bathroom faucets. However, you can also purchase separate faucet aerators and install them on faucets that are lacking aerators.

What Is a Faucet Aerator's Purpose?

Removing the aerator and tapping it out upside-down may release a small piece of grit or scale produced by the inside of the pipes. While an aerator does filter debris, this is not its main purpose. Rather, a faucet aerator improves the flow of water and helps it feel softer to the touch. By introducing small bubbles to the water, the faucet aerator allows the faucet to run longer while using less water.

  • Creates a wider stream of water
  • Lessens water splashing in the basin
  • Helps save water by making water flow more productive
  • Can additionally save water when a flow arresting aerator is installed
  • Bubbles activate soap faster, saving soap and water
  • Gives the water a softer feeling to the hands
  • Gives drinking water a lighter, fresher taste
  • Filters sediment

An aerator is not necessary and may even be counterproductive on some exterior faucets (such as for garden hoses), shower or bathtub faucets, or clothes washer water supply faucets.

How to Replace a Faucet Aerator

A faucet aerator can easily be replaced or installed with only two simple tools: pliers and a towel. Tongue and groove pliers (Channellock is one such brand) are the best type of pliers for this project. The towel should be small since you will be using it as a protective device when applying the pliers to the faucet aerator.

  1. With the towel, clean the inside thread of the faucet.

    Blue towel cleaning inside of faucet aerator

    The Spruce / Sarah Lee

  2. Ensure that the aerator is fully assembled. A faucet aerator especially must have the washer in place to prevent leakage.

    Fully assembled faucet aerator held in hand

    The Spruce / Sarah Lee

  3. Place the aerator into the end of the faucet until the threads catch.

    Aerator placed on end of faucet threads

    The Spruce / Sarah Lee

  4. Manually screw the aerator clockwise firmly into the faucet.

    Turning aerator clockwise to screw to faucet

    The Spruce / Sarah Lee

  5. Wrap the towel around the faucet aerator and tighten with the wrench.

    Faucet wrapped with blue towel and aerator tightened with wrench

    The Spruce / Sarah Lee

  6. Turn the water on full volume to test.


    Do not tighten the aerator too much or you risk stripping the threads on either the faucet or the aerator.

    Faucet running with flowing water to test aerator

    The Spruce / Sarah Lee

    How to Clean a Faucet Aerator

    Cleaning a faucet aerator can sometimes improve the flow of water by removing sediment, scale, or other grit from the mesh filter. Even if your water flow is satisfactory, you should clean it at least twice a year to maintain water freshness.

    1. Close the sink stopper to avoid losing parts down the drain.
    2. Remove the faucet aerator and place it on a clean towel.
    3. Take the aerator apart if possible.
    4. Soak the aerator in white vinegar (or CLR) for an hour.
    5. Remove the vinegar and rinse with fresh water.
    6. Replace the aerator on the faucet and turn on the water to test.