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18x18x1 MERV 13: pack prices & where to buy

Printed size 18x18x1 (square), MERV 13 only — actual about 17.75–17.81 × 17.75–17.81 × 0.75–0.78. Not 18x20x1 or 18x24x1. Lowest per filter on 16 Oct: Nordic Pure 24-pack at $10.00. Pick a pack below.

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Our pickNordic Pure 18x18x1 pleated (official via Awin)MERV 13 · Pack of 24$239.99$10.00 per filterLowest verified price per filter (MERV 13): $10.00 each, checked 16 OctBuy at Nordic Pure

Match & price

Full answer

Printed size is 18x18x1 — a square 1-inch-class furnace or AC filter. This page is only the MERV 13 slice of that size. Tonight (16 Oct 2026) we read Nordic Pure MERV 13 2-, 3-, 4-, 6-, 12- and 24-packs on nordicpure.com (via Awin) and a Nordic Pure MERV 13 6-pack and a Filtrete MPR 1900 6-pack on Amazon. The cut panel is smaller than the nominal size: the JB Tools listing for the Nordic Pure filter prints about 17.75 × 17.75 × 0.75, and the Filtrete MPR 1900 (MERV 13) Amazon title prints 17.81 × 17.81 × 0.78. Lowest per filter: the Nordic Pure 24-pack, $239.99 ($10.00 each). This is not an 18x20x1 (two inches longer) or an 18x24x1. Compare all MERV levels on the parent 18x18x1 size page.

Price check notes

Nordic Pure MERV 13 2/3/4/6/12/24-pack $34.99 / $43.99 / $54.49 / $69.99 / $129.99 / $239.99 ($17.50 / $14.66 / $13.62 / $11.67 / $10.83 / $10.00 per filter) — one-time purchase prices read on nordicpure.com product 18x18x1-air-filters on 16 Oct 2026 (~8:55pm ET, MERV 13 and each pack selected; SKUs 18x18x1M13-2 to 18x18x1M13-24; Nordic Pure does not offer a 1-pack in this size). Amazon (persistent checker profile, en-US, ZIP 10001, featured buy-box, 16 Oct 2026 ~9pm ET): Nordic Pure MERV 13 6-pack B005ESO1IU $69.99 ($11.67; sold by Amazon.com); Filtrete MPR 1900 (MERV 13) 6-pack B07FNQWZSC $108.99 ($18.17; sold by Amazon.com). No Prime-only price was shown. Honeywell Store 18x18x1 product URLs returned 404 when we built the parent page, so Honeywell is not listed.

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 18x18x1 pleated: about 17.75 × 17.75 × 0.75 (JB Tools listings for 18x18x1M13-2 and 18x18x1M13-6).
  • Filtrete 18x18x1 MPR 1900 (MERV 13): 17.81 × 17.81 × 0.78 (Amazon B07FNQWZSC title).
  • We did not find a Honeywell Store 18x18x1 1-inch filter, so Honeywell is not listed.

If you switch brands in a tight slot, 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 on the 18x18x1 page and ask an HVAC tech. More on ratings: MERV explained.

Where to buy (all stores)
  • Nordic Pure (official, via Awin) — MERV 13 2/3/4/6/12/24-pack cards above, prices read 16 Oct 2026.
  • Amazon — a Nordic Pure MERV 13 6-pack and a Filtrete MPR 1900 6-pack (cards above); or 18x18x1 MERV 13 search.
FAQ

Is 18x18x1 the same as 18x20x1? No. 18x20x1 is two inches longer; buy the size printed on your current filter.

Which pack is cheapest per filter? On 16 Oct, the Nordic Pure 24-pack ($10.00 per filter).

Sources
  • EPA MERV table: epa.gov/indoor-air-quality-iaq/what-merv-rating
  • Nordic Pure 18x18x1 MERV 13 2/3/4/6/12/24-pack $34.99 / $43.99 / $54.49 / $69.99 / $129.99 / $239.99, one-time purchase on nordicpure.com product 18x18x1-air-filters (read 16 Oct 2026, SKUs 18x18x1M13-2 to 18x18x1M13-24).
  • Amazon B005ESO1IU $69.99 (Nordic Pure MERV 13 6-pack, featured buy-box, read 16 Oct 2026).
  • Amazon B07FNQWZSC $108.99 (Filtrete MPR 1900 6-pack, featured buy-box, read 16 Oct 2026); actual size from the Amazon title.
  • Parent size page: 18x18x1.