Rheem Water Softeners
Bottom line
The Preferred RHS32 at $489 is the cheapest softener with a verified published price in our data, and the Preferred Plus RHS42 at $589 is the cheapest route to an 11 ppm iron rating, the highest we have recorded. Both are Home Depot exclusives. Neither lists third-party certification, which is the one thing the similarly priced GE units have.
Home Depot exclusive, and why that helps
Rheem sells these two through Home Depot rather than through its own storefront, and the practical effect is that the price is real and checkable. Our chart shows $489 and $589 because those are shelf prices rather than an MSRP with a rotating discount against it.
That is worth more than it sounds. Whirlpool and A.O. Smith leave pricing to the retailer and publish nothing, so their rows in our chart carry no price at all. SpringWell publishes a promotional price that has been running every time anyone looks. Rheem is the one brand here where the number you read is the number you pay.
Learning Technology, minus the marketing
Both units use what Rheem calls Learning Technology, which in plain terms is demand-initiated regeneration that adapts the salt dose to how much water the house has actually used. Every metered softener in our chart does some version of this. Rheem's contribution is the branding.
The numbers underneath are ordinary in a good way. The RHS32 is rated 33,000 grains at its maximum 14.1-pound dose and about 4,940 grains per pound at the 2.6-pound minimum. The RHS42 reaches 42,400 grains at 16.3 pounds and about 5,010 grains per pound at its 2.5-pound minimum. Those efficiency figures sit right alongside GE and Whirlpool.
The Preferred Plus also carries a built-in sediment filter and takes plumbing up to 1-1/4 inch, which matters on larger houses where a 3/4 inch service line would throttle flow before the softener did.
Every Rheem unit we track
| Model | Type | Capacity | Salt/regen | Flow | Certifications | Warranty | Price | |
|---|---|---|---|---|---|---|---|---|
| Rheem Preferred Plus RHS42 | salt-based | 42,000 gr | 16.3 lbs | 9.9 GPM | — | 1 yr parts/labor (extendable to 5), 3 yrs electronics, 10 yrs tanks | $589 | At The Home Depot |
| Rheem Preferred RHS32 | salt-based | 32,000 gr | 14.1 lbs | 7.9 GPM | — | 1 yr parts/labor (extendable to 5), 3 yrs electronics, 10 yrs tanks | $489 | At The Home Depot |
Specs read from manufacturer pages. Each unit's page lists its source and check date. “—” means not yet sourced, never guessed.
The certification gap
Neither Rheem product page lists an NSF or ANSI certification. GE's cabinet units, at $569 and $586, carry NSF/ANSI 44, NSF/ANSI/CAN 372 and WQA CSA B483.1. Whirlpool carries NSF/ANSI 44 on both WHES units.
So the $80 between the RHS32 and the GXSH40V buys an independently verified capacity claim. Whether that is worth $80 is a judgement call, and it cuts against Rheem more on paper than it probably does in a basement. The counter-argument is that GE has discontinued both of its models and Rheem has not.
Where to go from here
Brand matters less than size and type. Start with the capacity your household needs, then decide salt-based vs salt-free, and only then compare Rheem against the alternatives at that size in the full comparison chart.
Frequently Asked Questions
How much does a Rheem water softener cost?
The Preferred RHS32 is $489 and the Preferred Plus RHS42 is $589, both Home Depot exclusives, as checked in August 2026. Those are shelf prices rather than an MSRP, which makes Rheem the most price-transparent brand in our data.
Which Rheem softener is best for well water?
The Preferred Plus RHS42. Its 11 ppm iron rating is the highest published figure in our data, ahead of the A.O. Smith units and the Whirlpool WHES40 at 10 ppm. It also includes a sediment filter, which is useful on wells.
Is Rheem NSF certified?
Not according to its product pages. Neither the Preferred RHS32 nor the Preferred Plus RHS42 lists an NSF or ANSI certification, where GE and Whirlpool both cite NSF/ANSI 44. That does not mean the capacity claims are wrong, only that no independent body has verified them.