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18x20x1 MERV 13: pack prices & where to buy

Printed size 18x20x1, MERV 13 only — actual about 17.5–17.81 × 19.5–19.81 × 0.75–0.78 by brand. Not 20x20x1, 16x20x1 or 18x24x1. Lowest per filter on 19 Oct: Nordic Pure 12-pack at $11.25. Pick a pack below.

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Our pickNordic Pure 18x20x1 pleated (official via Awin)MERV 13 · Pack of 12$134.99$11.25 per filterLowest verified price per filter (MERV 13): $11.25 each, checked 28 OctBuy at Nordic Pure

Match & price

Full answer

Printed size is 18x20x1 — a 1-inch-class rectangle furnace or AC filter (the same panel is sometimes labeled 20x18x1). This page is only the MERV 13 slice of that size. Tonight (19 Oct 2026) we read Nordic Pure MERV 13 2, 3, 4, 6, 12 and 24-packs on nordicpure.com (via Awin), Honeywell Ultra Efficiency (MERV 13) 4- and 12-packs on the Honeywell Store, and Filtrete MPR 1900 (MERV 13) 2-packs on Amazon. The cut panel is smaller than the nominal size: Nordic Pure is about 17.5 × 19.5 × 0.75, Honeywell publishes 17.75 × 19.75 × 0.75, and the Filtrete MPR 1900 (MERV 13) Amazon title prints 17.81 × 19.81 × 0.78. Lowest per filter: the Nordic Pure 12-pack, $134.99 ($11.25 each) (the 24-pack is also $11.25 per filter). This is not a 20x20x1, 16x20x1 or 18x24x1. Compare all MERV levels on the parent 18x20x1 size page.

Price check notes

Nordic Pure MERV 13 2/3/4/6/12/24-pack $34.99 / $43.99 / $54.99 / $69.99 / $134.99 / $269.99 ($17.50 / $14.66 / $13.75 / $11.67 / $11.25 / $11.25 per filter) — one-time purchase prices read on nordicpure.com product 18x20x1-air-filter on 19 Oct 2026 (~8:57pm ET, MERV 13 and each pack selected; SKUs 18x20x1M13-2 to 18x20x1M13-24; Nordic Pure does not offer a 1-pack in this size). Honeywell 18x20x1 Ultra Efficiency MERV 13 4-pack $71.95 ($17.99) and 12-pack $197.95 ($16.50), Honeywell Store product pages read 19 Oct 2026 (in stock). Amazon (persistent checker profile, en-US, ZIP 10001, featured buy-box, re-read 25 Oct 2026 at ~10:27pm and again at ~10:29pm ET, same price): Filtrete MPR 1900 (MERV 13) 2-pack B0F9LTKG2W $42.56 ($21.28; sold by Amazon.com; it was $42.76 on 24 Oct, $42.86 on 23 Oct, $42.88 on 22 Oct, $42.52 on 21 Oct, $42.74 on 20 Oct and $42.45 on 19 Oct). No Prime-only price was shown.

Why MERV 13?

MERV 13 catches more fine particles (smoke, some bacteria, fine dust) than MERV 8 or 11, per the EPA MERV table. In a 1-inch filter that comes with more airflow resistance, so it suits systems that run well with a denser filter. Change it on schedule.

Actual size by brand
  • Nordic Pure 18x20x1 pleated: approximately 17.5 × 19.5 × 0.75 (17½ × 19½ × ¾; JB Tools listing for Nordic Pure 18x20x1M13-24, as recorded on the parent 18x20x1 page).
  • Honeywell 18x20x1 Ultra Efficiency (MERV 13): 17.75 × 19.75 × 0.75 (Honeywell Store product specs).
  • Filtrete 18x20x1 MPR 1900 (MERV 13): 17.81 × 19.81 × 0.78 (Amazon B0F9LTKG2W title “Act Size 17.81x19.81x0.78 in”; the same listing’s product-dimensions field says 19.81 × 17.81 × 0.81).

Switching from Nordic Pure (~17.5 × 19.5) to Honeywell or Filtrete gives a snugger slide-in. If the slot is tight, measure the old filter first: how to measure.

When not to buy MERV 13 in 1-inch

If your system manual limits filter resistance, or you notice weak airflow, a noisy blower or a frozen coil after switching, step down to MERV 8 or 11 on the 18x20x1 page and ask an HVAC tech. More on ratings: MERV explained.

Where to buy (all stores)
  • Nordic Pure (official, via Awin) — MERV 13 2, 3, 4, 6, 12 and 24-pack cards above, prices read 19 Oct 2026.
  • Honeywell Store — Ultra Efficiency MERV 13 4-pack and 12-pack cards above, prices read 19 Oct 2026.
  • Amazon — Filtrete MPR 1900 (MERV 13) 2-packs (cards above); or 18x20x1 MERV 13 search.
FAQ

Is 18x20x1 the same as 20x18x1? Yes — same panel, axes swapped. It is not a 20x20x1, 16x20x1 or 18x24x1; buy the size printed on your current filter.

Which pack is cheapest per filter? On 19 Oct, the Nordic Pure 12-pack ($11.25 per filter) (the 24-pack is also $11.25 per filter).

Is the Honeywell MERV 13 cheaper? Not per filter tonight: $17.99 (4-pack) and $16.50 (12-pack) versus $11.25 for the Nordic Pure 12-pack.

Sources
  • EPA MERV table: epa.gov/indoor-air-quality-iaq/what-merv-rating
  • Nordic Pure 18x20x1 MERV 13 2/3/4/6/12/24-pack $34.99 / $43.99 / $54.99 / $69.99 / $134.99 / $269.99, one-time purchase on nordicpure.com product 18x20x1-air-filter (read 19 Oct 2026, SKUs 18x20x1M13-2 to 18x20x1M13-24).
  • Honeywell Store 18x20x1 Ultra Efficiency MERV 13 4-pack $71.95 and 12-pack $197.95 (product pages, read 19 Oct 2026).
  • Amazon B0F9LTKG2W $42.56 (26 Oct; $42.39 before) (Filtrete MPR 1900 2-pack, featured buy-box, re-read 25 Oct 2026; $42.76 on 24 Oct, $42.86 on 23 Oct, $42.88 on 22 Oct, $42.52 on 21 Oct, $42.74 on 20 Oct, $42.45 on 19 Oct).
  • Actual sizes: Honeywell Store specs; JB Tools listing for Nordic Pure 18x20x1M13-24; Amazon B0F9LTKG2W title (as recorded on the parent page).
  • Parent size page: 18x20x1.