Filterbuy AFB18x20x1M8pk2 18x20x1 Air Filter, MERV 8, 2-Pack

If your furnace, air conditioner, heat pump, or HVAC system takes an 18x20x1 filter, this two-pack provides MERV 8 filtration in a pleated design. Its actual dimensions are 17.50 x 19.50 x 0.75 inches, so matching the measured filter size—not just the nominal label—helps you select the right replacement.

Electrostatically charged synthetic media is designed to capture dust, pollen, lint, and mold particles while supporting airflow. That makes this filter a practical choice for routine HVAC maintenance at home or in a business.

Fit and sizing

The 18x20x1 label is the nominal size, the actual size is 17.50 x 19.50 x 0.75 inches. If you have the existing filter, compare its dimensions with these measurements before ordering. Nominal sizes are rounded for easier shopping, while actual dimensions show the precise fit. The filter is designed for slide-in installation in compatible furnaces, air conditioners, heat pumps, air cleaners, and HVAC systems.

The two-filter pack is useful when you want a replacement ready for your next maintenance interval. Follow the airflow direction indicated for your system when inserting the filter, then reinstall the intake cover. Turn off power to the system before changing the filter.

What you’ll notice day to day

MERV 8 synthetic media uses an electrostatic charge and 14 pleats per foot to capture common airborne particles, including pollen, lint, and mold, as well as dust. The pleated surface gives the filter its filtration structure, while its stated design supports airflow during everyday HVAC operation. The manufacturer recommends replacing filters every 90 days as a general guideline, household conditions, including pets and allergy concerns, can affect the schedule.

Compared with choosing a filter by nominal size alone, this option makes the actual dimensions easy to identify, which can help when matching a replacement to the filter currently in your system. Customers often highlight straightforward installation and dust and pollen capture. Feedback on fit and sizing is mixed, making the listed actual measurements especially useful when checking compatibility.

Tech specs

• Type: Pleated HVAC air filter
• Nominal size: 18 x 20 x 1 inches
• Actual size: 17.50 x 19.50 x 0.75 inches
• MERV rating: 8
• Media: Electrostatic synthetic
• Pack size: 2 filters
• Compatible equipment: Air cleaner, air conditioner, furnace, HVAC system, heat pump
• Maximum velocity: 615 cfm
• Maximum temperature: 200 °F
• Made in: USA

Questions before you buy

What is the difference between the nominal and actual size? The nominal size is the rounded 18x20x1 label. The actual size is 17.50 x 19.50 x 0.75 inches and gives the filter’s precise dimensions for fit.

Which systems is this filter designed for? It is listed for use with compatible air cleaners, air conditioners, furnaces, HVAC systems, and heat pumps. Match the actual size to the filter your system requires.

How often should I replace it? The general recommendation is every 90 days. Conditions such as pets, allergy concerns, and household needs can affect how often replacement is appropriate.

Is it worth it?

For shoppers who need an 18x20x1 nominal replacement, this Filterbuy two-pack combines MERV 8 pleated filtration with dimensions that make size matching clear. Its synthetic media is designed to capture common household particles, and the compatible equipment range covers several everyday HVAC applications. Choose it when the actual 17.50 x 19.50 x 0.75-inch measurements match your system and you want a pair of filters for ongoing maintenance.