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20x20x3 MERV 13: pack prices & where to buy

Printed size 20x20x3, MERV 13 only. Lowest per filter on 4 Nov: FiltersDelivered Zephyr VGF 3-pack at $39.98 each. These are 3-inch return-grille “top-hat” filters (Zephyr VGF): the gasket fills a 20×20 grille and the media is about 18⅜ × 18⅜ × 3.

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Match & price

All MERV levels (MERV 10, 11 and 13) and the full fit table: 20x20x3 size page. A 20x20x4 or 20x20x5 media cabinet is a different part: 20x20x4 MERV 13 · 20x20x5 MERV 13. Thinner slot? See 20x20x2 MERV 13 or 20x20x1 MERV 13.

Full answer

A 20x20x3 is a three-inch-class square filter. The common home version is a return-grille “top-hat”: a gasket seats in a 1-inch 20×20 return grille and about 3 inches of pleated media hangs into the duct. On 4 Nov 2026 the cheapest MERV 13 per filter was the FiltersDelivered Zephyr VGF 3-pack at $39.98 each. Match the depth and face of the filter you pull out.

Which slot do I have?
  • 20×20 return grille that takes a 3-inch top-hat filter: this is the size. The Zephyr VGF cards above are sold for that use.
  • Plain 20×20 grille with a 1-inch filter: a 20x20x1 fits; a top-hat may work only if the duct behind the grille has room for the extra depth. If unsure, stay with 20x20x1 MERV 13.
  • Old filter about 4–4⅜ inches thick in a furnace cabinet: that is a 20x20x4 or 20x20x5 media cartridge, not this one.
  • Honeywell FC313R2020: Honeywell Home lists it as a 20×20 MERV 13 return-grille filter (19.75 × 19.75 × 3.13); we have no verified price for it, so it has no card. See Honeywell FC313R. The MERV 10 Honeywell FC40R1003 is on the 20x20x3 size page.

Measure the old filter before you order: how to measure.

Price check notes

FiltersDelivered (Zephyr 20x20x3 VGF MERV 13 “Case of 3” product page, in stock, read 4 Nov 2026 ~8:56pm ET and again ~9:10pm): $119.95 (sale price; the page also shows a $139.95 list price). The FiltersDelivered 2-pack and the MERV 11 case on the parent page are not verified tonight. Coupons, multi-pack discounts and Subscribe & Save prices are not counted.

Why MERV 13?

Per the EPA MERV table, MERV 13 captures at least 50% of 0.30–1.0 µm particles, 85% of 1.0–3.0 µm and 90% of 3.0–10.0 µm, versus MERV 8’s ≥20% of 1.0–3.0 µm. EPA suggests at least MERV 13 or as high as your system fan and filter slot can accommodate, and to ask an HVAC technician if unsure. A 3-inch MERV 13 is not HEPA. Check it when the season changes and replace it when it looks gray.

Actual size by brand
  • Zephyr VGF M1332020 MERV 13: actual 18.375 × 18.375 × 3 behind a gasket that fills a 20-inch grille (Jackson Systems, J Adams product copy).
  • Honeywell Home FC313R2020 MERV 13: 19.75 × 19.75 × 3.13 (Honeywell Home specs) — a different cut; measure the grille pocket (see the 20x20x3 size page).
Where to buy (all stores)
  • FiltersDelivered Zephyr VGF — MERV 13 3-pack card above, read 4 Nov 2026.
  • Amazon: a search on 4 Nov (~9:18pm ET) showed a Zephyr-branded 20x20x3 VGF MERV 13 single (ASIN B0F6NNJ37H, $49.95 in the search results) and several no-name “compatible with Zephyr VGF” 2-packs. We did not get two buy-box reads for the Zephyr listing and do not list unbranded look-alikes, so there is no Amazon card yet.
  • Nordic Pure had no 20x20x3 product page when we checked (4 Nov), so it is not listed.
  • Honeywell Home FC313R2020 (MERV 13): no verified price, no card.
FAQ

Is a 20x20x3 the same as a 20x20x2? No. A 20x20x2 furnace-slot pack is about 1.75 inches deep and will not fill a 3-inch return-grille depth.

Which pack is cheapest per filter? On 4 Nov, the FiltersDelivered Zephyr VGF 3-pack ($39.98 per filter).

Can I use a 20x20x4 instead? No. A 4-inch-class cartridge is about 3.6–4.4 inches deep and is built for a furnace media cabinet, not a return grille. Match the depth of your old filter.

How often do I change it? Zephyr sells the VGF as a 6-month filter; check it every season and replace it sooner if it looks gray, with pets, smoke or renovation dust. See how often to change.

Sources