A. O. Smith AO-WH-FILTER

Last updated: November 2, 2026

A. O. Smith AO-WH-FILTER
3.6/5#1 of 6 in tank whole-house filters
3.6

A certified, maintenance light tank for a small or medium home on chlorinated city water.

  • $0.67 per 1,000 galRunning cost
  • 600,000 gallonsCapacity
  • 7 gpmFlow
  • NSF/ANSI 42Certified
Check price at Amazon$399

Price checked November 2, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros
  • NSF certified for chlorine taste and odor, rare among tank filters
  • Rated for 600,000 gallons, years of use in most homes
  • No drain or power needed; it never backwashes
  • The lowest priced tank system here
Cons
  • Rated 7 gpm through 3/4 in ports, tight for a big house
  • Needs a separate sediment pre-filter, sold separately
  • No price published for the replacement element

How it scores

The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its build. How we rank explains each one.

Specifications

Model numberAO-WH-FILTER
Filtration
Capacity600,000 gallons
Replacement filters or media$399
Running cost$0.67 per 1,000 gal
Stages1
CertifiedNSF/ANSI 42
ChloramineNo
PFASNo
Build
Flow7 gpm
Ports0.8 in
BackwashingNo
UV stageNo
Warranty6 years

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