Filters

Reset

20x20x4 Air Filter

Nominal Size
Actual Size
Merv Rating

Bulk Quantity Pricing

4 6 12 48 72 120
Quantity

19.5x19.5x4

MERV 8

$11.64 $10.48 $10.24 $9.89 $8.73 $8.15

19.5x19.5x4

MERV 13

$25.16 $22.64 $22.14 $21.39 $18.87 $17.61

19.5x19.5x4

MERV 11

$17.37 $15.63 $15.29 $14.76 $13.03 $12.16

🛡️ 20x20x4 Air Filters – Strong Protection, Cleaner Air, Efficient HVAC

The 20x20x4 Air Filter from Custom Filters Direct is built to improve your home's air quality while boosting your HVAC system's performance. With its thick pleated design and strong filtration power, it captures airborne particles like dust, pet hair, and pollen — making it a great option for families, pet owners, and allergy sufferers alike.

This filter fits most HVAC systems including furnaces, central air units, and heat pumps. It's a powerful choice for anyone looking to reduce allergens, odors, and airborne debris while maintaining a comfortable and energy-efficient home.

💨 Why Choose the 20x20x4 Air Filter?

  • Great Filtration Performance: Available in MERV 8, 11, and 13 to effectively trap dust, pollen, and pet dander
  • Universal HVAC Compatibility: Fits a wide range of systems — just verify sizing for your unit
  • Precision Fit: Actual size is 19.5 x 19.5 x 4", ensuring a snug seal that filters all incoming air
  • Improves Airflow: Helps your system run efficiently and use less energy
  • Odor Control: Helps reduce lingering odors for fresher indoor air

🔍 Product Specs at a Glance

  • Size: 20 x 20 x 4 inches (actual: 19.5 x 19.5 x 4”)
  • MERV Ratings: Choose from MERV 8, MERV 11, or MERV 13
  • Recommended Replacement: Every 3–6 months depending on usage and air quality
  • Filter Media: Pleated, electrostatic material for enhanced particle capture
  • Frame: Moisture-resistant, durable construction for long-term reliability

🏠 Ideal For:

  • Homes with pets or allergy sufferers
  • Kitchens or living spaces prone to odors
  • Furnaces, central air systems, and HVAC units that support 4-inch filters
  • Energy-conscious households

⚙️ MERV Rating Comparison: Which Should You Choose?

MERV Rating Captures Best For
MERV 8 Dust, pollen, lint Standard protection for most homes
MERV 11 Pet dander, mold spores, smoke Homes with pets or mild allergies
MERV 13 Bacteria, fine particles, virus carriers High-efficiency filtration for allergy-sensitive households

🧼 Maintenance Tips for Peak Performance

  • Check Monthly: Inspect the filter for buildup and replace as needed
  • Replace Every 3–6 Months: More frequently in homes with pets, cooking odors, or high dust
  • Ensure Proper Fit: Always confirm actual dimensions (19.5 x 19.5 x 4") match your unit
  • Don’t Reuse: Always replace used filters — they lose efficiency over time

❓ FAQs About 20x20x4 Air Filters

What is the actual size of the 20x20x4 filter?

The true size is 19.5” x 19.5” x 4”. Be sure to measure your filter slot before purchasing to ensure a snug fit.

How often should I replace this filter?

We recommend replacing it every 3–6 months, depending on air quality, pets, and HVAC usage.

What’s the difference between MERV 8, 11, and 13?

MERV 8 is ideal for general filtration. MERV 11 is better for pet dander and smoke, while MERV 13 provides top-tier protection against fine particles and allergens.

Can this filter reduce odors?

Yes — by trapping odor-causing particles, the 20x20x4 filter helps improve freshness throughout your home.

Is this filter reusable?

No — this is a disposable filter. Replacing it regularly ensures consistent performance and air quality.

🛒 Shop 20x20x4 Filters from Custom Filters Direct

Ready to upgrade your air quality? The 20x20x4 Air Filter is your go-to solution for fresher air and better HVAC performance. Choose your MERV level, get fast shipping, and enjoy the confidence that comes with cleaner indoor air — all from Custom Filters Direct.