Kenmore 350
A compact, certified demand softener for one to four people, though the same design costs less under other brands.
Amazon $621.29$621.29
The Kenmore 350 rates 3.1 among up to 32,000 grains water softeners; the Kenmore 420 rates 2.8 among 32,001 to 48,000 grains ones. The Kenmore 350 costs $201.48 less ($621.29 vs $822.77).
Kenmore 420
A certified 40,000 grain demand softener for well or city water, but the price is hard to justify against similar models.
Amazon $822.77$822.77
Prices were last checked November 1, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different size classes (up to 32,000 grains and 32,001 to 48,000 grains), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.
| Factor weight | Kenmore 350 | Kenmore 420 |
|---|---|---|
| Overall rating | 3.1/5 | 2.8/5 |
| Value 30% | 55 $19.42 per 1,000 grains ($621.29, 32,000 grains) | 34 $20.57 per 1,000 grains ($822.77, 40,000 grains) |
| Salt efficiency 20% | 50 salt efficiency not published (neutral score used) | 50 salt efficiency not published (neutral score used) |
| Flow 15% | 20 7.2 gpm service flow | 0 7.7 gpm service flow |
| Warranty 25% | 22 3 years on the valve, 10 years on the tanks | 22 3 years on the valve, 10 years on the tanks |
| Certification 10% | 100 certified to NSF/ANSI 44 | 100 certified to NSF/ANSI 44 |
Specifications
| Kenmore 350 | Kenmore 420 | |
|---|---|---|
| Capacity | ||
| Rated capacity | 32,000 grains | 40,000 grains |
| Service flow | 7.2 gpm | 7.7 gpm |
| Control | ||
| Valve | Kenmore demand valve | Kenmore demand valve |
| Regenerates on demand | Yes | Yes |
| App or remote monitoring | No | No |
| Certification and warranty | ||
| NSF/ANSI 44 | Yes | Yes |
| Valve warranty | 3 years | 3 years |
| Tank warranty | 10 years | 10 years |