Whole house water filter system cost
Whole house water filter installation cost ranges from $850 to $5,400 for a whole-house filtration system, according to HomeGuide's 2026 data. System type and what's in your water decide the price.
| Whole-house filtration system, installed (HomeGuide) | $850–$5,400 |
| Well water filtration system, installed (HomeGuide) | $800–$4,000 |
| Whole-house reverse osmosis, installed (HomeGuide) | $4,800–$8,000 |
| UV treatment system, installed (HomeGuide) | $350–$1,500 |
| Water softener, installed (HomeGuide) | $1,200–$3,800 |
| Under-sink filter, installed (HomeGuide) | $170–$580 |
| Under-sink reverse osmosis (HomeGuide) | $300–$950 |
Test before you buy
The right system depends on what is actually in your water. City water customers can read their utility's annual water quality report; well owners should have the water tested. Sediment, chlorine taste, hardness, iron and bacteria each call for different equipment, and buying more treatment than you need is the most common way to overspend.
Whole-house vs. point-of-use
A whole-house (point-of-entry) system treats all water entering the home, which protects pipes and appliances and helps with problems like sediment or chlorine in showers. A point-of-use filter, such as under-sink carbon or reverse osmosis, treats only drinking water and costs far less. Many homes pair a basic whole-house sediment/carbon filter with an under-sink RO unit for drinking water.
Hard water is a separate problem
Filters don't remove hardness minerals; a softener does. See water softener installation cost.
Ongoing costs
Budget for replacement cartridges and media, UV lamps on UV systems, and salt for softeners. Ask the installer for the replacement schedule and current part prices before you buy, so the long-term cost is clear.
Installation details that add cost
- Bypass valves and shutoffs so the system can be serviced.
- Drain connections for backwashing or RO systems.
- An electrical outlet for UV units.
- Space and access near the main water line.
Frequently asked questions
How much does a whole house water filter cost installed?
HomeGuide puts whole-house filtration systems at $850 to $5,400 installed in 2026.
How much is a whole house reverse osmosis system?
HomeGuide lists whole-house RO at $4,800 to $8,000 installed, versus $300 to $950 for under-sink RO.
Do I need a whole house filter for well water?
Depends on test results. HomeGuide prices well water filtration at $800 to $4,000 installed.
Will a water filter fix hard water?
No. Hardness is treated with a softener, which HomeGuide prices at $1,200 to $3,800 installed.
Related cost guides
Sources
National figures from published 2026 cost guides, retrieved 10 Oct 2026. Local prices, especially in high-cost metros, can be higher. Always get written quotes.