RO systems handle contaminants that whole-house filters can't, like arsenic, fluoride, and dissolved solids. Here's what one actually costs, and why well water needs extra prep before RO.
| System Type | Typical Cost |
|---|---|
| Under-sink RO (drinking water only) | $150–$400 |
| Under-sink RO with remineralization | $200–$500 |
| Whole-house RO / combo bundle | $1,000–$2,700 |
RO membranes are fine enough to remove dissolved solids, but that also means they clog quickly if sediment or iron reaches them unfiltered. Well water systems need sediment and carbon pre-filter stages ahead of the RO membrane — most consumer RO systems for well water bundle this in already.
RO doesn't fix everything. RO is excellent for drinking water quality but isn't typically used to treat whole-house iron or hardness — that's what dedicated filters and softeners are for. RO is usually the last stage, not the first.
Pre-filters need replacement every 6-12 months (roughly $20-$40 per set), and the RO membrane itself typically lasts 2-3 years (around $30-$50 to replace). Budget $50-$100 annually for upkeep on a typical under-sink system.
Under-sink RO systems typically cost $150-$400. Whole-house RO systems and combo bundles that include RO alongside filtration and softening run $1,000-$2,700.
Yes. Well water often carries sediment and iron that can clog RO membranes quickly without pre-filtration. Most RO systems for well water include sediment and carbon pre-filter stages built in.
RO membranes typically last 2-3 years, while pre-filters need replacement every 6-12 months. Budget $50-$100 annually for replacement filters and membranes.
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