Ultrasonic diffusers work in a similar way to nebulizing diffusers by creating a fine mist. The difference is that ultrasonic diffusers use water and essential oils to create an ultrasonic cool mist of water/oils that releases into the air. They double as a humidifier, so they are beneficial in winter, but they don’t put out as strong of a concentration of essential oils since they also use water.
Note: It is not recommended to use citrus essential oils with this type of diffuser as they can cause the parts to erode.
Less expensive than nebulizing diffusers
Doubles as a humidifier (beneficial in cold months)
Many options to choose from
Doesn’t use heat
Water tank has a large capacity
Can’t use citrus essential oils
Need water to operate
Must be cleaned occasionally
Some have lights that can’t be turned off
Not as effective as nebulizing diffusers