Holmes offers replacement filters for its purifiers and humidifiers in wick, activated carbon, and HEPA media. True HEPA typically removes 99.97% of 0.3-micron particles, but overall purifier performance depends on the unit design. Replace filters on the schedule in your manual and match part numbers for proper fit and performance.
Holmes filter lineup and compatibility
Holmes sells a range of replacement filters for its air purifiers and humidifiers. Replacement filters are made to fit specific Holmes models so you can swap them without modifying the unit. Holmes also offers companion products - fans, heaters, humidifiers, and lighting - under the same brand family.
If you own a Holmes purifier or humidifier, check the model number on the unit or in the manual before buying a replacement filter. Models and filter part numbers change over time, and using the correct filter keeps the unit effective and may preserve any product warranty.
Filter types and where they're used
Holmes commonly offers three types of replacement media:
- Wick filters: used in evaporative humidifiers to absorb water and release moisture into the air. They trap mineral deposits and need periodic replacement to avoid odors and reduced performance.
- Activated carbon filters: designed to reduce odors, some gases, and volatile organic compounds (VOCs). Carbon filters are usually paired with particulate filters in purifiers.
- HEPA filters: designed to capture very small particles such as dust, pollen, pet dander, and many smoke particles.
What is HEPA?
HEPA stands for high-efficiency particulate air (or arrestance). In consumer products, a "True HEPA" filter typically removes at least 99.97% of particles at 0.3 microns, which is the most penetrating particle size for many filters. HEPA media captures particles through a mix of interception, impaction and diffusion.
Government agencies and health organizations recommend HEPA filtration for reducing airborne particles indoors, but performance depends on the full purifier design (fan, seals, airflow) as well as the filter itself.
Choosing and replacing filters
Replacement filters for small-room purifiers and humidifiers often range from modest to moderate prices depending on filter type and model. Wick filters for humidifiers are usually less costly than true HEPA cartridges, while combined HEPA-plus-carbon cartridges cost more. Prices change with retailer and model, so compare part numbers before purchase.
Most manufacturers recommend replacing filters on a schedule: wick filters every 1-3 months depending on water quality and usage; carbon filters and HEPA cartridges every 6-12 months depending on air quality and run time. Follow the device manual for the exact interval.
Practical tips
- Always match the exact replacement part number.
- Keep spare filters on hand if you run the purifier year-round.
- Consider prefilters or washable screens to extend HEPA life.
- Recycle or dispose of used filters according to local waste rules.
- Confirm current corporate owner/parent company of the Holmes brand (ownership has changed historically). [[CHECK]]
- Verify typical retail price ranges for Holmes replacement filters (wick, carbon, HEPA) as of 2025 to replace the placeholder pricing statement. [[CHECK]]
- Confirm the authoritative source for the HEPA performance specification (99.97% at 0.3 microns) and whether that is the formal definition used by US agencies. [[CHECK]]