Best Filterless Air Purifiers (2021 Review)

If you’ve been shopping for a filterless air purifier, and you’re trying to figure out which is best for you, then you’re in the right spot!

In this proHVACinfo guide, you will learn the following:

  • What are filterless air purifiers? (why filterless purifiers may be best for you )
  • What are the different types of filterless air purifiers? (watch out for this one thing!)
  • How do air filterless air purifiers work? (why they’re different from other purifiers)
  • What do you look for in the best filterless air purifiers? (what separates the best from the rest)

And much more!

Below you’ll find a quick list of our top 5 recommendations, keep scrolling to learn more:

  1. IonPacific IonBox (Our Top Pick)
  2. Airfree P3000 (Best High-End)
  3. Germ Guardian Pluggable Air Purifier And Sanitizer (Best Budget)
  4. HAPHiD Negative Ion Generator
  5. Airfree T800 Filterless Air Purifier

Our Overall #1 Rated Pick

The IonBox from IonPacific took top prize in this list for a few reasons.


First of all, we loved the compact design.

Why should you only have clean, purified air in your home? This portable unit can come with you in the car, to a hotel, to your office, pretty much anywhere you could ever possibly want to breathe clean air.

It’s very well made, and extremely efficient. In fact, it only draws a miniscule 1.5 watts of power during operation, so it can even operate when plugged into a laptop USB power source.

Negative ion technology has proven success when it comes to air purification, so it’s no surprise that this compact unit can tackle odors, allergens, viral particles and bacteria with ease.

What Are Filterless Air Purifiers?

Filterless air purifiers are next generation air sanitizing devices used in homes, commercial spaces, and even some vehicles, to reduce, and in some cases, eliminate harmful airborne particles, contaminants, pathogens, and even odors.

They offer an alternative to traditional filtered purifiers for those who perhaps aren’t great at remembering to change filters, or, who simply don’t want the ongoing expense or hassle of filter replacement at regular intervals.

By choosing a filterless air purifier, you get a one and done purchase, without losing the cleaning power.

This style of air purifier comes in a range of shapes and sizes, and offer cleaning for many room sizes.

What Are The Different Types Of Filterless Air Purifier?

There are a few different technologies in use across the field of filterless air purifiers, each of them working very differently from the others.

Electrostatic Precipitators

Electrostatic precipitators make use of electrodes and electrically charged plates to remove dust and large particles from the air. A high voltage charge is run through the electrodes, which in turn charge the dust and other airborne particles that pass by them. The charged particles are then attracted to the oppositely charged plate, which captures and removes them from the atmosphere.

Ultraviolet Light Purifiers

Ultraviolet, or UV, light is well known and highly regarded for its sanitizing properties. This light can kill harmful pathogens like viruses and bacteria as contaminated air passes through the light. Because it is capable of killing bacteria, UV purifiers can also reduce odors caused by these germs.

Ionizing Air Purifiers

Ionizing air purifiers work by creating positively or negatively charged molecules known as ions. These ions are then send out by way of a fan into the room, where they attach themselves to airborne particles, weighing them down until they land upon a surface, and thus removing them from the atmosphere.

TSS Thermodynamic Purifiers

TSS stands for thermodynamic sterilization, a technique that involves heating a ceramic core to almost 400 degrees Fahrenheit. When air passes through these purifiers, almost all mold spores, viral particles, or bacteria are almost instantly obliterated, leaving clean air to pass out of the other side.

A Word About Ozone Generators

Ozone generators are sometimes sold as air purifiers. The idea behind these devices is that they absorb oxygen from the air and give it an electrical charge.

This charge rearranges the molecules, adding a third oxygen molecule, effectively turning O2 into O3.

These purifiers push O3, or ozone, into the surrounding air. When the ozone contacts airborne contaminants, it binds to, and destroys them.

However, the effectiveness and even safety of ozone generators has been a long-standing topic of debate between the EPA and vendors that sell them.

The EPA has found that ozone, when inhaled, can be harmful to the lungs.

For that reason, we recommend avoiding the use of ozone generators marketed at air purifiers.

With so many other great options, why risk using a device that could be harmful?

For that reason, none of the products we have reviewed emit ozone when used as directed.

How do Filterless Air Purifiers Work?

Filterless air purifiers avoid the use of MERV, HEPA, and Activated Charcoal filtering media to provide you with air sanitization that doesn’t require replacement or cleaning of filters.

By taking advantage of the high tech cleaning methods listed above, filterless purifiers can remove contaminants, pathogens, and odors from the air as efficiently as purifiers with traditional filters.

What Do You Look For In The Best Filterless Air Purifiers?

When you’re dealing with different technologies, it’s hard to give an apples to apples guide of what to look for, but there are of course some standard “must haves” when it comes to selecting a filterless air purifier

Coverage Area

This is a fairly simple feature to look for, but one of the most important.

Filterless air purifiers should be rated for a certain size of room, measured in square feet, or square meters in some cases.

The greater the area of coverage, the better – provided that it checks the boxes on the other top features to look for.

Energy Efficiency

You may save money on avoiding filter replacements with these purifiers, but if they draw a lot of power, you’ll be spending it in electricity bills.

Models with low energy consumption ratings not only cost you less money over their lifetimes, but can often be plugged into USB outlets, giving you a more flexibility in how you use them.

Noise Levels

The quieter the better! Many of the filterless air purifiers available today are completely silent, thanks to their lack of a fan.

A quiet purifier is more likely to be left running day and night, meaning your air is constantly being cleaned.

Noisy purifiers tend to get turned off at night, but as dirty, contaminated air never takes a break, this is a big factor to bear in mind.

Particle Reduction

An indication of a good purifier is a baseline particle reduction rating of 99%. Think carefully before purchasing anything with a lower rating than that.

Our Reviews Of The Best Filterless Air Purifiers

IonPacific IonBox (Our Top Pick)

For something so tiny, this thing really packs a punch! Within just 30 minutes, the IonBox can saturate a 500 square foot room with sanitizing negative ions. When these ions get to work, they’ll remove pet dander, smoke particulate, dust, and even food odors from the air.

Because of its small size, you really can take it anywhere, in fact, it’s compact enough to fit in a pocket. It’s solidly made, it looks good, and the USB power makes I easy to find a place to plug it in wherever you go.


  • Effective ionization
  • Avoids black marks on walls
  • Factory tested ion count


  • Some fan noise
  • Not rechargeable

Airfree P3000 (High-End Pick)

The Airfree O3000 is the most expensive model on test by quite some margin, but we think the price is justified. This purifier uses TSS thermodynamic sanitizing to incinerate airborne particles and contaminants.

Because of the TSS technology, there are no fans required, making this a completely silent purifier, an ideal choice for anybody concerned about noise. It boasts a sleek design, including an adjustable night light. To top it all off, the build quality is superb, and is made with pride in the European Union.


  • 2 Year warranty
  • No Ozone or UV emmittance
  • Low running costs


  • Expensive
  • Instruction manual not well written

Germ Guardian Pluggable Air Purifier And Sanitizer (Best Budget Pick)

The Germ Guardian is a handy little filterless air purifier that plugs directly into a socket. It makes use of ultraviolet light technology for its sanitization properties, and the bulbs can last for up to a year. It has a tiny footprint, measuring just 7 inches in height, and weighing in at 0.7 pounds.

The UV light kills many pathogens, including influenza, staph, and rhinovirus, and is also capable of neutralizing household odors from pets and cooking.


  • Excellent price
  • Convenient design


  • Fragile bulb
  • Needs high humidity for best results

HAPHiD Negative Ion Generator

The HAPHiD Negative Ion Generator is a fantastic little plug in purifier that very much deserves its place on this top 5 filterless air purifiers list. It’s available with either a silver or gold frame, and because of its slim, flat shape, it blends nicely on any wall.

This ionizer works without a fan, so it’s completely silent, which makes it a great choice for bedrooms. What makes this such great value for money is that it comes in a 3 pack, meaning you can keep the air purified in 3 rooms for one low price.


  • Comes in a 3 pack
  • No parts to replace


  • Large unattractive logo
  • Weak at odor neutralizing

Airfree T800 Filterless Air Purifier

This is another excellent TSS type air purifier from Airfree. Air enters the device and is heated to 400 degrees Fahrenheit, sterilizing it before it is recirculated into the room. The fanless design keeps energy consumption low, and while not as small as some of the other filterless air purifiers on test, it’s still very much in the portable category.

It’s a beautifully designed piece of equipment, and as we’ve come to expect from Airfree, it’s very well made, too.


  • Efficient thermodynamic sanitizing
  • Effectively neutralizes odors


  • Not multivoltage
  • Easily knocked over

Final Thoughts On The Best Filterless Air Purifiers

Filterless air purifiers make sense for many reasons.

While HEPA and MERV 13 filtered purifiers have their advantages, like any device using a filter media, from the first moment you turn it on, it continually loses effectiveness until it’s completely clogged.

Filterless purifiers like those on test in this proHVACinfo guide don’t have that particular issue.

They offer a great way to keep the air in your home clean and odor free, without the inconvenience of having to remember to change filters.

Filterless air purifiers offer unmatched efficiency, and much quieter operation than other types of air sanitizing devices.

Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

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Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

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