Pentair XXX-10422
A NSF-certified under-sink filter that is certified to reduce 3 contaminants at about 0.8¢ per gallon.
As an Amazon Associate we earn from qualifying purchases — disclosure. Price as of July 15, 2026; check Amazon for the current price.
You want strong contaminant reduction at the kitchen tap without a countertop unit, and are comfortable with a simple under-cabinet install.
Certified to reduce 3 contaminants.
Like most carbon filters, it does not remove fluoride — only reverse osmosis does that.
What is under-sink filter? A carbon-based cartridge (or set of stages) plumbed under your kitchen sink that filters the cold drinking-water line. Compare all filter types →
What it costs to own
| Upfront price | $159.47 |
| Replacement filter (XXX-122TO5 XXX-122TO5S) | $159.47Buy refill → |
| Estimated yearly cost (filters, ~1.5×/yr) | ~$239/yr |
| True cost per gallon | 0.8¢ |
Cost per gallon and yearly cost are our estimates from the rated capacity and current prices. The filter only works if you replace it on schedule.
What it's certified to remove
Certification is per-contaminant: the Pentair XXX-10422 is credited only for the contaminants listed here, verified by NSF. It does not imply removal of anything not listed.
✓ Verify this certification on the official NSF listing →
Full specifications
| Certified by | NSF |
| NSF/ANSI standards | 42 — reduces taste, odor, and chlorine (aesthetic standard) · 53 — certified for health contaminants such as lead, VOCs, and cysts |
| Filter type | Under-sink filter |
| Rated capacity | 20,000 gallons |
| Flow rate | 2.5 gpm |
| Replacement element | XXX-122TO5 XXX-122TO5S |
| Installation | Mounts under the sink; connects to the cold line. Basic DIY. |
Frequently asked
Is the Pentair XXX-10422 NSF certified?
Yes — the Pentair XXX-10422 is listed in the NSF certified-product database under NSF/ANSI standards 42, 53. That means an independent body verified its claims (not just "tested to" a standard).
What does the Pentair XXX-10422 remove?
It is certified to reduce 3 contaminants: Chlorine / chloramine, Cryptosporidium, Giardia.
How much does the Pentair XXX-10422 cost per gallon?
About 0.8¢ per gallon, based on its rated capacity of 20,000 gallons and current price.
How often do you replace the under-sink filter?
A under-sink filter like this is typically replaced about 2 time a year (replacement element XXX-122TO5 XXX-122TO5S). Replace on schedule — a spent cartridge stops reducing contaminants.
Compare similar under-sink filters
Source: NSF public certification listing. Specs and certified claims are from the official listing; cost figures are our estimates. Some links are affiliate links — see our disclosure.