Home / Sizes / 16x20x4

Size page

16x20x4 air filter: actual size, MERV, and price

A 16x20x4 is a four-inch-class media filter for a dedicated cabinet — not a 1-inch return slot. Buy the printed size 16x20x4. Do not substitute a 16x20x1. The cartridge is smaller than 16 by 20 by 4 inches, and actual depth varies more by brand than it does on 1-inch panels: Honeywell F100/F200 replacements are about 4⅜ inches thick; Filtrete 4-inch SKUs print about 4.31 inches; Nordic Pure’s 16x20x4 is about 3⅝ inches (3.63). Measure the old cartridge.

Same panel, swapped axes: 20x16x4. We treat 16x20x4 as the canonical label. Order 16x20x4. A 16x20x5 Honeywell-replacement SKU is a different listing (often 4⅜ inches actual depth sold under a 5-inch name) — do not mix the two by title alone.

Actual size by brand

These numbers are copied from manufacturer or merchant product copy, not from a competitor size chart. Thickness is part of the fit: a Honeywell F100/F200 cabinet takes a ~4⅜ inch cartridge; a 3⅝ inch “16x20x4” will sit short in that box.

Brand Nominal Published actual (in.) Source
Honeywell FC100A1003 (F100 / F200 / F150 media cabinet, MERV 11) 16x20x4 15.875 × 19.875 × 4.375 (15⅞ × 19⅞ × 4⅜) Air Quality Honeywell Store product copy (“Exact Dimensions: 15 7/8 x 19 7/8 x 4 3/8”); AllFilters FC100A1003 specs
Honeywell Home CF200A1620 Ultra Efficiency (MERV 12) 16x20x4 15.90 × 19.75 × 4.38 Honeywell Store product specs (“Exceeds Honeywell FC100A1003 specifications”)
BestAir HW1620-8R Honeywell cabinet replacement (MERV 8) 16x20x4 15.75 × 19.75 × 4.375 (15¾ × 19¾ × 4⅜) True Value product specs; Home Depot product bullets for HW1620-8R
Filtrete 16x20x4 MPR 1550 / MERV 12 16x20x4 15.88 × 19.88 × 4.31 Amazon B086DYVPW2 title and “exact dimensions”
Filtrete 16x20x4 MPR 1900 / MERV 13 16x20x4 15.44 × 19.75 × 4.31 Amazon B0DCGS1B21 title and “exact dimensions”
Nordic Pure 16x20x4 pleated 16x20x4 Approximately 15.5 × 19.5 × 3.63 (15½ × 19½ × 3⅝) JB Tools listings for 16x20x4M8-2, 16x20x4M8-6, 16x20x4M13-2, and 16x20x4M13-6

If you currently run a Honeywell FC100 / F100 / F200 cartridge (~4.38 inches thick) and switch to Nordic Pure’s 16x20x4 (~3.63 inches thick), the pack will not fill the cabinet. Nordic Pure’s own 16x20x4 copy says to order their 16x20x5 Honeywell replacement (published 15.88 × 19.75 × 4.38) when the old filter is 4⅜ inches deep. Filtrete’s two 16x20x4 SKUs also disagree with each other on face size (15.88 vs 15.44). Measure the old filter. Full method: how to measure.

MERV 8 vs 11 vs 13 (facts only)

MERV is ASHRAE 52.2, as summarized by EPA. Higher MERV captures a larger share of smaller particles. It also adds resistance. EPA says to pick at least MERV 13 or as high a rating as your system fan and filter slot can accommodate, and to ask an HVAC technician if you are unsure. A 4-inch MERV 13 is not HEPA. We do not claim health outcomes.

MERV EPA average capture efficiency (particle size) Typical 16x20x4 use
8 ≥20% of 1.0–3.0 µm; ≥70% of 3.0–10.0 µm Common pleated replacement in a 4-inch rack or cabinet when the manual does not call for higher
11 ≥20% of 0.30–1.0 µm; ≥65% of 1.0–3.0 µm; ≥85% of 3.0–10.0 µm OEM Honeywell FC100A1003 media-cabinet cartridge is labeled MERV 11
13 ≥50% of 0.30–1.0 µm; ≥85% of 1.0–3.0 µm; ≥90% of 3.0–10.0 µm Higher-efficiency 4-inch; confirm the air handler can take the extra pressure drop. Not HEPA

Source: U.S. EPA, “What is a MERV rating?”, last updated 14 Jan 2026. Filtrete also prints an MPR number; MPR is 3M’s scale, not MERV. Compare MERV to MERV. Honeywell CF200A1620 and Filtrete MPR 1550 are labeled MERV 12 — between the EPA 11 and 13 rows above; we do not invent a MERV 12 EPA line.

Pack prices checked 30 Aug 2026

These are public shelf/cart prices we recorded on 30 Aug 2026. They are not live. Shipping, subscribe-and-save, and store-only deals will move them. Per-filter math is pack price ÷ count, rounded to the cent.

Listing MERV Pack Price that day Per filter Merchant
Nordic Pure 16x20x4 pleated (reseller) 8 6 $103.49 $17.25 JB Tools
Nordic Pure 16x20x4 pleated (reseller) 8 2 $37.34 $18.67 JB Tools
Honeywell FC100A1003 OEM media (F100/F200) 11 2 $53.00 $26.50 Amazon
Honeywell Home CF200A1620 Ultra Efficiency 12 1 $30.29 $30.29 Honeywell Store
Filtrete 16x20x4 MPR 1550 12 2 $61.83 $30.92 Amazon
Nordic Pure 16x20x4 pleated (reseller) 13 6 $134.99 $22.50 JB Tools
Nordic Pure 16x20x4 pleated (reseller) 13 2 $50.39 $25.20 JB Tools

Observed range that day for ordinary pleated 16x20x4: about $17.25–$18.67/filter at MERV 8 in Nordic Pure multi-packs (3⅝ inch actual depth — not a Honeywell F100 fill), $26.50 at MERV 11 for the OEM FC100A1003 2-pack, $30.29–$30.92 at MERV 12 (Honeywell CF200A1620 single; Filtrete MPR 1550 2-pack), $22.50–$25.20 at MERV 13 in Nordic Pure multi-packs. Cabinet-depth (~4⅜ inch) replacements cost more per filter than the 3⅝ inch Nordic Pure cut. Amazon’s Filtrete MPR 1900 / MERV 13 2-pack (B0DCGS1B21) loaded with printed actuals but no featured offer, so that pack price is omitted rather than guessed. Target’s BestAir 16x20x4 3-pack page (A-90978107) loaded without a public cart price in the fetch; Home Depot’s BestAir HW1620-8R page returned a bot check — those pack prices are omitted rather than guessed. Target had no Filtrete 16x20x4 listing (16x25x4 and 20x20x4 Filtrete 4-inch pages exist instead). Amazon Basics has no 16x20x4 SKU with a printed actual. Walmart product pages were not used for a price row.

Where to buy

We may earn a commission if you buy through links on this page. It does not change the price you pay.

No ranking. Stock and price change. If the slot is an odd fraction that none of these actual sizes match, measure first — that is not a 16x20x4 SKU. A 16x20x1 or a 16x20x5 is not a substitute by name alone.

Sources (accessed 30 Aug 2026)