Point of entry: whole-home
A whole-home system is installed on the incoming household water supply. Water is treated before it is distributed to connected household outlets.
This makes sense when the homeowner’s goal involves multiple taps, showers, bathrooms, laundry or one central treatment point.
Point of use: under-sink
An under-sink system treats water at one location, typically a dedicated drinking-water tap. It can be a simpler and more targeted option when the main concern is drinking and cooking water.
Point-of-use systems can also use technologies, such as reverse osmosis, that are usually not applied to every litre entering the house.
Neither is automatically better
The better architecture depends on the outcome. Whole-home treatment is about broad household coverage. Under-sink treatment is about focused drinking-water treatment. Some households may use both.
Questions to ask
- Do you want treatment at one drinking tap or throughout connected outlets?
- Is the concern chlorine taste/odour, sediment, hardness, dissolved salts or something specific?
- Do you want a true softener?
- Is wastewater, electricity or storage acceptable for the chosen technology?
- What maintenance and replacement filters are required?
Sources and last reviewed
Last reviewed: September 2026.
This article is general educational information and does not replace water testing, utility advice, plumbing advice or health advice for a specific circumstance.
