Direct answer: SpringWell’s salt-based softeners come in three sizes: the SS1 (1–3 bathrooms, 32,000 grains, 11 gpm), SS4 (4–6 bathrooms, 48,000 grains, 13 gpm) and SS+ (7+ bathrooms, 80,000 grains, 20 gpm). The same softeners are sold paired with a whole-house carbon filter as the CSS1, CSS4 and CSS+ combos, and SpringWell’s MMV-1 and MMV-4 2-in-1 systems put filtration and softening in one tank. The FutureSoft FS1, FS4 and FS+ are salt-free scale-prevention systems that do not remove hardness. On October 15, 2026, listed prices ran from $1,606.50 (SS1) to $4,284 (CSS+) during a 15% promotion.
Publisher boundary: Water System Guide is an independent research publisher, not a SpringWell retailer or affiliate. Specifications and prices come from SpringWell’s product pages and SS-series installation guide, reviewed October 15, 2026. Prices are dated and change with SpringWell’s promotions. Bathroom ranges are SpringWell’s sizing labels, not our recommendation.
Salt-based softeners: SS1, SS4 and SS+
SpringWell’s specification table (salt softener product page):
| SS1 | SS4 | SS+ | |
|---|---|---|---|
| Bathrooms | 1–3 | 4–6 | 7+ |
| Grain capacity | 32,000 | 48,000 | 80,000 |
| Service flow | 11 gpm | 13 gpm | 20 gpm |
| Tank | 9” x 48” (57” with head) | 10” x 54” (63”) | 13” x 54” (63”) |
| Connection | 1” | 1” | 1” |
| Backwash rate | 2 gpm* | 2.4 gpm* | 4 gpm |
| Operating pressure | 25–80 psi | 25–80 psi | 25–80 psi |
| Temperature | 36–120°F | 36–120°F | 36–120°F |
| pH | 6.5–10 | 6.5–10 | 6.5–10 |
| Brine tank | 18” x 33” round | 18” x 33” | 18” x 33” |
| Price, Oct 15, 2026 (regular) | $1,606.50 ($1,890) | $1,785 ($2,100) | $2,677.50 ($3,150) |
*SS1 and SS4 backwash rates are from the installation guide (PDF page 4); the product page lists a backwash rate only for the SS+.
All three share one model page on this site, the SpringWell salt-based water softener. The installation guide’s recommended settings differ only in grains capacity (32 or 48) and brine refill (8 or 10 minutes); both use a 14-day day override, 10% reserve and 2:00 a.m. regeneration. See our SpringWell regeneration guide.
SpringWell’s sizing note on the product page: “It’s not only about bathroom count. It’s about how many things run at once.” The SS+ is described as “built for the highest demand - multiple showers, appliances, and fixtures running at once, with no drop-off.”
Filter + salt softener combos: CSS1, CSS4, CSS+
The combos pair a whole-house filter tank (CF1, CF4 or CF+) with the matching SS softener (combo product page). The filter tanks:
| CF1 | CF4 | CF+ | |
|---|---|---|---|
| Bathrooms | 1–3 | 4–6 | 7+ |
| Capacity | 1,000,000 gallons | 1,000,000 gallons | 1,000,000 gallons |
| Tank | 9” x 48” | 10” x 54” | 13” x 54” |
| Service flow | 9 gpm | 12 gpm | 20 gpm |
| Connection | 1” | 1” | 1.5” |
| Pre-filter change | Every 6–9 months | Every 6–9 months | Every 6–9 months |
| Tank height with head | 52” | 58” | 58” |
| Operating pressure | 25–80 psi | 25–80 psi | 25–80 psi |
| Media replacement | Every 10 years or 1 million gallons | Same | Same |
Prices on October 15, 2026: CSS1 $2,231.25 (regular $2,625), CSS4 $2,499 ($2,940), CSS+ $4,284 ($5,040). The page carries a “do not use where water is microbiologically unsafe” note for the filter. Model page: SpringWell water filter + salt softener combo.
Note that the CF1 is rated at 9 gpm while the SS1 is rated at 11 gpm, and the CF4 at 12 gpm against the SS4’s 13 gpm. In a combo, the lower of the two ratings is the practical limit.
2-in-1 filter + salt softener: MMV-1 and MMV-4
The 2-in-1 puts filtration and softening in a single tank (2-in-1 product page):
| MMV-1 | MMV-4 | |
|---|---|---|
| Bathrooms | 1–3 | 4–6 |
| Filter capacity | 500,000 gallons | 1,000,000 gallons |
| Grain capacity | 32,000 | 48,000 |
| Tank | 10” x 54” | 13” x 54” |
| Service flow | 11 gpm | 15 gpm |
| Backwash rate | Not listed | 4 gpm |
| Connection | 1” | 1” |
| Operating pressure | 25–80 psi | 25–80 psi |
| pH | 6.5–10 | 6.5–10 |
| Brine tank | 18” x 33” round | 18” x 33” round |
| Price, Oct 15, 2026 (regular) | $2,286.48 ($2,689.98) | $2,833.09 ($3,333.05) |
Compared with the CSS combos, the 2-in-1 uses one tank instead of two, but the MMV-1’s filter is rated for half the gallons of the CF1. Model page: SpringWell two-in-one filter softener.
FutureSoft salt-free: FS1, FS4, FS+
FutureSoft is listed under water softeners but is a salt-free scale-prevention system (FutureSoft product page):
| FS1 | FS4 | FS+ | |
|---|---|---|---|
| Bathrooms | 1–3 | 4–6 | 7+ |
| Service flow | 12 gpm | 15 gpm | 20 gpm |
| Tank | 6” x 35” | 9” x 48” | 13” x 54” |
| Pressure | 20–80 psi | 20–80 psi | 20–80 psi |
| pH | 7.0–9.5 | 7.0–9.5 | 7.0–9.5 |
| Hardness max | 81 gpg | 81 gpg | 81 gpg |
| Iron, manganese, copper, oil, H2S | 0 | 0 | 0 |
| Free chlorine max | 3 ppm | 3 ppm | 3 ppm |
| Price, Oct 15, 2026 (regular) | $1,785 ($2,100) | $1,963.50 ($2,310) | $2,320.50 ($2,730) |
SpringWell’s own comparison text on the salt softener page puts the trade-off plainly: the salt-free option needs “no salt, no sodium, no drain, no electricity,” but “won’t make water feel slick or stop spotting the way salt does.” Our SpringWell salt softener vs FutureSoft comparison goes deeper. Model page: SpringWell FutureSoft.
Well water combinations
SpringWell also sells a well-water filter paired with a salt softener. Because the installation guide says “do not install on well water unless you have spoken to a customer service representative first,” and the warranty sets well-water conditions, well owners should start with a water test and a call to SpringWell. Model page: SpringWell well filter + salt softener combo.
What every SS-series box shares
The SS1, SS4 and SS+ ship with the same parts list. SpringWell’s installation guide shows a 50-foot drain line, two MNPT fittings, two 1-inch, 24-inch-long corrugated water connectors, a 1-inch, 3-inch-long PVC nipple and a roll of plumber’s tape. The bypass valve is marked “sold separately” (installation guide, PDF page 2).
The guide also says “it is highly recommended to install a 3-valve bypass around the softener system (not included)” if the bypass valve was not purchased. Without a bypass, it says, “the main water supply must be turned off” any time the system is serviced, and “a licensed plumber can install a 3-valve bypass using standard tee fittings and ball valves” (PDF page 3). On October 15, 2026, SpringWell’s bypass add-on was $58.79, as listed in our cost guide.
Because the parts list, brine tank, pressure range and settings screens are the same across the three sizes, the choice between SS1, SS4 and SS+ is mostly a choice of grain capacity, tank size and flow rate. The installation guide’s setup steps do not change by model except for the grains-capacity and brine-refill values.
Reading the bathroom labels
SpringWell sizes every line by bathroom count: 1–3, 4–6 and 7+. Its own product copy then adds that sizing is “not only about bathroom count. It’s about how many things run at once.” Read the flow rate as the real limit. If two showers, a washing machine and a dishwasher can run together in your home, compare that peak demand with the 11, 13 and 20 gpm ratings rather than relying on the bathroom count alone.
Grain capacity matters for how often the softener regenerates, not for flow. A larger tank in a small home regenerates less often; a small tank in a hard-water home with a large family regenerates more often. Our regeneration guide covers how the capacity, reserve and day-override settings interact.
Choosing between them
- Hardness only, municipal water: an SS model sized for peak flow.
- Hardness plus chlorine taste and odor: a CSS combo or an MMV 2-in-1. The combo has more filter capacity; the 2-in-1 saves space.
- Scale control without salt or a drain: FutureSoft, if your water meets its zero-iron, zero-manganese limits and you accept that water will not be softened.
- Large homes: SS+ (80,000 grains, 20 gpm) or CSS+, noting the CF+ uses a 1.5” connection.
For prices and running costs see the SpringWell cost guide; for the company and support see who makes SpringWell water softeners.
Frequently asked questions
What is the difference between the SpringWell SS1 and SS4?
Size. The SS1 is rated for 1–3 bathrooms, 32,000 grains and 11 gpm in a 9” x 48” tank. The SS4 is rated for 4–6 bathrooms, 48,000 grains and 13 gpm in a 10” x 54” tank. Both use the same 18” x 33” brine tank and limits.
Is SpringWell FutureSoft a water softener?
Not in the ion-exchange sense. SpringWell lists it with its softeners, but its own comparison says FutureSoft won’t make water feel slick or stop spotting the way salt does. It needs no salt, drain or electricity.
What is the SpringWell CSS combo?
A whole-house carbon filter tank (CF1, CF4 or CF+) paired with the matching SS salt softener. The filter is rated for 1 million gallons, with pre-filter changes every 6–9 months.
Which SpringWell softener is the largest?
The SS+, rated for 7+ bathrooms, 80,000 grains and 20 gpm in a 13” x 54” tank. On October 15, 2026, it listed at $2,677.50 during a 15% promotion, against a regular $3,150.