Quick answer: All four companies sell US-made pleated air filters. FilterBuy and Nordic Pure bundle freight into the filter price and offer subscriptions (5% and 10% off). Discount Filters ships free over $70. Ironside does it differently: $14.95 flat shipping that stays the same on 1, 2 or 3 packs, no subscription — stock the year, pay freight once.
First things first: we sell filters. This is a first-party comparison — read it accordingly. We've kept every claim checkable against each company's own site.
The comparison
| Ironside | FilterBuy | Nordic Pure | Discount Filters | |
|---|---|---|---|---|
| Made in USA | Yes, by our manufacturing partners | Yes | Yes | Yes (house brands) |
| MERV range | 6–16 | 8–13 + odor eliminator | 6–16 | 8–13 and up |
| Carbon options | Yes — at nearly every MERV level | One odor variant | Yes | Limited |
| Subscription | No — packs instead | Yes, 5% off | Yes, 10% off | Not a focus |
| Shipping | $14.95 flat — same on 1, 2 or 3 packs | Built into price ("free") | Built into price ("free") | Free over $70 |
| Cheapest way to buy | Stack multi-packs on one flat rate | 6-packs | Subscribe + multi-pack | Clear the $70 bar |
Where each one wins
FilterBuy is the volume player — four US factories, fast free delivery, dominant content library. If you want one filter shipped tomorrow with zero math, they're good at that. The trade: a narrower MERV range (8–13) and freight hidden in the price.
Nordic Pure has the deepest catalog in the business — MERV 6 through 16 with carbon at nearly every level. If you know exactly what you want, they stock it. Their pitch is the 10% subscription; our math says packs beat it (below).
Discount Filters is the bargain aggregator — house brands, $70 free-shipping bar, broad but shallow. Good prices if your cart clears the bar.
Ironside is built around one idea: filters are a stock-up product, not a subscription product. Same American-made pleated media, MERV 6–16 with carbon options, and shipping priced honestly — $14.95 flat whether you buy 1, 2 or 3 packs.
The subscription math
A 10% subscription discount on a $20 filter saves you $2 per delivery. Ship four times a year and you've paid freight four times — it's in the price whether the invoice says so or not. Buy a year's worth in one order (say, a 4-pack plus a carbon 2-pack) and you pay $14.95 in freight once. The per-filter cost drops more than any subscription discount we've seen. Full math in our bulk buying guide.
FAQ
Which air filter company is best?
All four sell legitimate US-made pleated filters — the difference is how you pay. FilterBuy and Nordic Pure build freight into the filter price and push subscriptions (5% and 10% off). Discount Filters ships free over $70. Ironside charges $14.95 flat shipping that stays the same on 1, 2 or 3 packs, so a year’s supply costs the least per filter in one order.
Is an air filter subscription worth it?
Usually not. A 5–10% subscription discount is smaller than the freight you pay across repeated small shipments. Buying a year of filters at once — multi-packs on one flat shipping charge — beats a subscription on price, and a calendar reminder replaces the delivery schedule.
Are Ironside filters made in the USA?
Yes — Ironside filters are American-made by our manufacturing partners, with electrostatic synthetic media in heavy-duty frames, MERV 6 through MERV 16, including activated-carbon options.
Why does Ironside charge shipping when competitors ship free?
"Free" shipping is freight hidden in the per-filter price. Ironside prices the filter and the freight separately: $14.95 flat, same on 1, 2 or 3 packs. Order more at once and the shipping cost per filter keeps dropping.