Holds a Master’s degree in Engineering and is keen on her own home’s climate. Sometimes we think that Carolina owns every single product she writes about – that’s how profound and insightful her reviews always are.
For 8 years, Richard had been working as an HVAC specialist and AC unit installer since his student years. Now, he’s our main consultant on every technical aspect that may arise during our tests and research.
Last updated: July 08, 2021
Humidifiers are a lifesaver in fluctuating climate which makes us prone to dry skin, chapped lips, nasal congestion, sinus headaches, and asthma attacks. The best warm mist humidifier will provide you with more protection because, unlike cool mist humidifiers, it heats water to a boiling point before emitting it as steam. The high temperature is effective in destroying mold and harmful microorganisms and allows you to dispense medical inhalants which clear congestion and lower flu infections.
So what should you look for when shopping for the best warm mist humidifier? We have reviewed the key features to consider in order to get the maximum value out of your purchase. We first analyzed the coverage area because it indicates the size of the room or home that the unit can adequately protect without getting overwhelmed. Secondly, we assessed the weight and dimensions to determine the storage and portability of the unit. The third feature we evaluated was the tank capacity which has a direct influence on the overall runtime and the frequency of refilling. Lastly, we examined the noise level because it can either make your humidifier a tranquil companion or a waste of money.
This review has a comparison table ranking the best warm mist humidifier models on the market, based on a detailed analysis of their individual features, overall performance, and feedback from verified buyers, experts and other authoritative sites. The buying guide delves deeper into the key features to consider when shopping for a warm mist humidifier and the pros and cons of owning one. We provide more answers in the FAQ section and a summary of our top three choices.
Top 5 Warm Mist Humidifiers Review 2021
LEVOIT LV600HH – Editor’s Choice
Coverage area: up to 753 sq. ft.
Water tank capacity: 1.5 gal.
Aromatherapy option: yes
Runtime: up to 36 hours
Dimensions: 11.3 x 7 x 10.5 inches
More features: remote control; built-in humidity sensor; cleaning brush included
This is the best rated warm mist humidifier by verified buyers, expert reviewers and retailers such as Amazon. It has versatile features, a high moisture output rate, expansive coverage, large capacity, and a remote control for more convenience.
Levoit LV600HH increases moisture levels in areas with coverage of up to 753 square feet, which makes it the best warm mist humidifier for large rooms. It has an impressive runtime of 36 hours and an accurate built-in humidity sensor which detects the current humidity levels and automatically adjusts the level of moisture output to achieve optimal humidity. This means you can leave it running for almost the entire weekend while you are away.
The spacious water tank has a large capacity of 1.5 gallons which lessens the frequent need to refill, and the auto shut-off feature prevents damage when water is depleted. The unit has an LED screen and intuitive buttons on a digital panel which allow you to adjust the speed of mist output, program the timer to specific humidification duration, and set your preferred humidity. The selected settings are displayed on the LED screen. A remote control with labeled buttons enables you to operate the humidifier from a distance.
As a hybrid humidifier, Levoit LV600HH is capable of generating both warm and cool mist which can get rid of mold and microorganisms as well as reduce nasal congestion and respiratory ailments making it a perfect humidifier for sinus problems. The ultrasonic technology also makes it one of the best quiet warm mist humidifiers for large bedrooms, producing less than 36 decibels. You can add essential oils for a calmer, restful night.
Surprisingly, this unit only weighs 4.92 pounds. It is made of durable ABS plastic which is leak-proof. A cleaning brush is included in the package for the weekly cleaning of mineral buildup.
Vicks Warm Mist Humidifier – Best Value Warm Mist Humidifier
Coverage area: medium to large rooms
Water tank capacity: 1 gal.
Aromatherapy option: yes, Vicks VapoSteam
Runtime: up to 12 hours
Dimensions: 12 x 7.9 x 14.2 inches
More features: inbuilt tank handle; filter-free; 2 output settings; medical cup for liquid inhalants
This is the best warm mist humidifier for a baby’s nursery or bedroom because you can use it with Vicks VapoSteam which you put into the medical cup for liquid inhalants to generate medicated vapor to relieve coughs and congestion that babies are vulnerable to due to their undeveloped immunity system. You can also add essential oil inhalants like peppermint or eucalyptus for soothing sleep and additional therapeutic benefits. Another feature that makes it suitable for nurseries and bedrooms is the whisper-quiet operation since it does not use a fan.
Despite its expansive coverage of medium to large rooms with protection which lasts up to 12 hours owing to its one-gallon water tank capacity, the unit is compact in size and only weighs 4.25 pounds which makes it easy to set up or move it from one room to another.
The reservoir is transparent so you can keep an eye on the water supply. Once the water is depleted, the auto shut-off feature automatically turns the unit off to prevent damage. The built-in tank handle allows easy refilling.
This humidifier does not have a humidistat to automatically detect and correct humidity levels. However, there are two output settings of low and high which you can select according to your humidity needs.
It is an affordable filter-free humidifier which will save you money on filter replacement. All you need is to clean it with vinegar to remove any mineral buildup. Using distilled water to refill the tank will reduce the accumulation of residue.
Bionaire Ultrasonic Warm and Cool Mist Humidifier – Best Warm and Cool Mist Humidifier
Coverage area: medium to large rooms
Water tank capacity: 2 gal.
Aromatherapy option: no
Runtime: several days on low
Dimensions: 13 x 13.2 x 12.5 inches
More features: 3 humidity output settings; demineralization cartridge included
This versatile model combines the best features of warm and cool mist humidifiers to protect you in all seasons. You can either select the warm mist setting which removes impurities and destroys microorganisms or the cool mist option which saves energy. You can further save on utility bills by programming the built-in timer to run the unit for 4, 8, or 12 hours.
The best advantage of this warm mist ultrasonic humidifier is that, unlike evaporative models which heat water and emit it as steam that could cause scalding, it uses high-frequency vibration to break down water particles and generate ultra-fine mist of room temperature. This fine mist is dispersed faster to increase the moisture levels of medium and large rooms. The adjustable nozzle allows you to direct the mist to specific areas.
The six-pound humidifier comes with a large water tank with a capacity of two gallons which lets the unit operate for several days on low humidity output setting. The other humidity output options are medium and high intensity.
Since this model does not use a filter, it is more prone to buildup of white mineral deposits which are increased if you use hard water. A demineralization cartridge is included in the package to fix this. You will need to replace this cartridge after every 60 to 90 days, which adds extra costs.
A downside of this humidifier is that it does not work with medical inhalants like Vicks or essential oils for aromatherapy.
More features: filter free; 2 moisture output settings; light indicator when needs a refill
Those looking for a budget option will be thrilled by this one which can increase moisture levels in a medium-sized room for up to 24 hours. This is facilitated by the one-gallon water tank capacity and protective features such as the light indicator which illuminates to alert you when the tank is due for a refill and the auto shut-off feature which turns the unit off to prevent damage once the water runs out.
The water tank is made of transparent material to monitor water supply and has a built-in handle and a top-fill design for easy refilling.
This humidifier for essential oil has a medicine cup at the top, so you can add your favorite scents like lavender which improve your ambiance and also have a calming effect. Besides, you can add medical inhalants to clear sinuses and nasal congestion.
The filter-free model has two settings to regulate the rate of moisture output to your desired level. You can select a setting with the manual knob which is easy to operate.
This humidifier can fit in limited spaces because of its small size and low weight of five pounds. It also runs relatively quietly, although a few owners have noticed a bubbling sound when the water is heating.
Holmes Warm Mist Humidifier – Best Small Warm Mist Humidifier
Coverage area: small rooms
Water tank capacity: 1.2 gal.
Aromatherapy option: no
Runtime: up to 24 hours
Dimensions: 14.4 x 13.8 x 7.6 inches
More features: dishwasher safe; 2 comfort settings; filter free
Designed for small rooms, this model can operate for up to 24 hours without requiring refilling thanks to the water tank with a capacity of 1.2 gallons. Although it is quite compact, this is a fantastic humidifier for eczema. The auto shut-off feature turns the humidifier off when the tank is empty for safety purposes.
To refill the tank, you have to remove it and take off the cap at the bottom. This bottom-fill design is slightly inconvenient, but buyers do not seem to mind it because the opening is large and you can fit in your arm for thorough scrubbing. Cleaning the heating element is also a breeze because, unlike other models which have it integrated into the base, it hangs down into the water and can be easily removed and cleaned with white vinegar to remove mineral buildup. The removable parts are also dishwasher safe for added convenience.
The unit weighs only five pounds and comes with a handle for easy movement and two comfort settings to adjust the humidity level in your room to your preference. Since it is filter-free, you will save money on filter replacement.
Unfortunately, this humidifier is not compatible with essential oils and other inhalants. A few buyers also noted that the water tank cracks easily so you may have to be more cautious when handling it. As for performance, there are several reviews lauding its effectiveness in increasing moisture levels.
Why are we impressed?
Easy to clean
Compact and light
What negatives must you be aware of?
No aromatherapy option
Inconvenient bottom-fill design
Fragile water tank
Things to Consider
This guide lists the benefits and drawbacks of warm mist humidifiers and explores the main features you should evaluate before making your purchase. It also provides answers to common questions in the FAQ segment.
Advantages and disadvantages of warm mist humidifiers
Warm mist humidifiers use high temperature which kills bacteria and other harmful microorganisms.
They are effective in alleviating nasal congestion because the warm mist can easily penetrate the thin, mucous membrane.
They can be diffused with essential oils like lavender, peppermint, tea tree oil or eucalyptus to improve your mood, sleep, and ambiance. This also adds a pleasant fragrance to your environment.
Similarly, you can add liquid medical inhalants like Vicks VapoSteam which acts as a decongestant to relieve coughs and breathing problems.
Warm mist humidifiers run quietly because they generally do not use a fan.
They can also warm the room a bit in cold
The hot water and emitted steam are potentially dangerous for kids and pets. Watch them not to tilt the unit to avoid accidents.
The heating element can run up your energy bill.
Features to consider while choosing a warm mist humidifier
The following are the key features to consider when selecting the best warm mist humidifier for your needs.
It is essential to identify the size of the room where you will use the humidifier in order to invest in a model that can adequately protect the entire room. Manufacturers indicate the designated coverage area of their models to ensure you get the right one for your room or home. For example, Holmes Warm Mist Humidifier is suitable for small rooms while LEVOIT LV600HH can effectively increase moisture levels in large areas with coverage of up to 753 square feet.
Water tank capacity
A large water tank increases the amount of time that the warm mist humidifier can run without requiring refilling. This subsequently reduces the frequency of refilling, saving you time and effort. For instance, Bionaire Ultrasonic Warm and Cool Mist Humidifier has a two-gallon tank which operates the unit for several days while Honeywell HWM705B and Holmes Warm Mist Humidifier with a capacity of one gallon and 1.2 gallons respectively last for a maximum of 24 hours.
Bear in mind that the size of the tank will affect the overall weight of the unit, especially when full.
This refers to the length of time that a humidifier can operate on a full tank without requiring refilling. A water tank with a large capacity will obviously keep the unit running for longer.
Other factors that affect runtime include the speed and amount of moisture output, with a high speed depleting the reservoir faster and reducing the overall runtime.
The presence of fans, especially in evaporative models, increases the amount of noise generated by a humidifier. On the other hand, ultrasonic models like Levoit LV600HH use high-frequency vibrations which are barely audible to the human ear. The 36 decibels produced by this model is noiseless, equivalent to a night in a desert.
Setting the speed and moisture output to a lower level can substantially reduce the noise.
Dimensions and weight
All the models in this review can be considered portable humidifiers due to their small size and low weight which hardly goes beyond six pounds. However, warm mist humidifiers designed for entire homes are generally larger with massive water tanks. Knowing the size of space where you intend to install the unit can help you to identify the dimensions of humidifier.
The length, terms, and conditions of the warranty will depend on the model and the manufacturer.
One of the major things that void the warranty of humidifiers is adding inhalants and essential oils to the water tank instead of the medicine cup, or adding these scented oils in models that do not have this option. This is why our review clearly indicates the models with the aromatherapy option like Honeywell HWM705B, and the ones without it, such as Holmes Warm Mist Humidifier.
Confirm with the manufacturer or seller whether the unit can also work as an oil diffuser before adding essential oils. You can also check out reviews from other buyers.
Auto shut-off feature: This is a safety feature which turns off the unit when the tank is empty to prevent damage and fire accidents.
Timer settings: They let you set your preferred duration of humidification to conserve energy. Bionaire Ultrasonic Warm and Cool Mist Humidifier has a built-in timer that can set the unit to run for 4, 8 or 12 hours.
Humidistat: In addition to detecting the existing humidity levels, an integrated humidity sensor automatically adjusts the moisture output to improve and optimize humidity to the desired level. Adjustable speed: This gives you more flexibility in controlling the amount of moisture output and allows you to choose a lower speed to increase runtime and reduce noise level and energy consumption.
Filters: While filters are effective in purifying air and preventing clogging of the unit, they can add up extra costs in replacement. The models on our list are all filter-free. Instead, they use warm mist to destroy mold and microorganisms. The lack of filters predisposes them to mineral deposits when used with hard water so that you may require demineralization cartridges or regular cleaning with white vinegar.
Controls: This refers to the mode of operation and the ease of use. Modern designs like Levoit LV600HH feature a touchscreen panel with intuitive digital buttons for selecting and adjusting various settings and an LED screen which displays the selected ones. It also has a remote control to operate the humidifier from a distance. On the other hand, Honeywell HWM705B uses a manual knob to select the settings.
Aromatherapy option: As you have noticed in our review, some models like Holmes Warm Mist Humidifier do not have this capability which allows you to add medical inhalants, soothing scents, and essential oils to relieve respiratory problems and improve your mood and ambiance.
Warm mist humidifiers do contain the heating element to boil water before emitting it into the air. However, it’s compactly sealed inside the machine so won’t damage anyone if used correctly. Nevertheless, be sure you watch your kids and pets not to tilt it as it can lead to spillage and potential short circuit.
The optimal humidity level in your home should range between 40 to 50 percent.
LEVOIT LV600HH tops several review lists as the best rated warm and cool mist humidifier. It topped our list for its dual warm and cool mist functionality, convenient digital controls with an integrated humidistat and a remote control to boot, no pun intended. Its superior performance includes broad coverage, large water tank capacity, and a high moisture output rate.
Vicks V745A earned the second spot because it offers the best value in terms of affordable pricing, wide coverage, a sizeable tank with decent runtime and an option to add essential oils which are diffused into your room for soothing scents to improve your sleep quality.
We loved the versatility of Bionaire Ultrasonic Warm and Cool Mist Humidifier which makes up for the absence of an aromatherapy option with a massive two-gallon water tank which can improve humidity levels in your home for several days without requiring refilling. It also has a built-in timer which conserves energy, three settings to give you greater control of the moisture output intensity, and an adjustable nozzle which focuses humidification on a specific area.