Water Systems
Water Filters
Point-of-use filtration covers a wide range of formats, from a simple pitcher in the fridge to a dedicated under-sink system. Here's how the main formats differ, and where to go for a deeper buying guide on each.
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What's in this category
No plumbing needed — gravity-fed or faucet-diverter units that sit next to the sink.
Connects to the cold line beneath the sink, usually feeding a dedicated small faucet.
Clips directly onto an existing kitchen faucet — the fastest, cheapest way to filter tap water at the source.
Built into the fridge's water/ice line — convenient, but proprietary to the fridge model and brand.
Portable, fridge-door filtration with no installation — the entry point for most households.
The recurring consumable behind every system above — capacity (gallons or months) varies widely by cartridge.
Sized and threaded specifically per system — always match the cartridge to your exact filter model.
Top picks in this category
We are still verifying product picks for drinking-water filters, and we only list products after an editor has checked them. Until then, here is how to build a shortlist that fits your home.
- Independent certification. Look for NSF/ANSI certification for the contaminants you care about: 42 covers taste and odor, 53 health-related contaminants such as lead, 58 reverse osmosis, 401 emerging compounds. A marketing claim is not a certification.
- Your water report. Check your utility's annual water quality report or run a lab test first, so you buy for the contaminants you actually have.
- Rated capacity and cost. Divide the cartridge price by its rated gallons to compare true running costs across models.
- Flow and fit. Check the flow rate and whether it fits your sink, counter or fridge shelf.
Frequently asked questions
Which filter format removes the most contaminants?
It depends on the specific filter media and certification, not the format alone — a premium multi-stage pitcher or countertop filter can outperform a basic single-stage under-sink unit. Check the model's NSF/ANSI certification against the contaminants you care about.
How do I know which replacement filter I need?
Match the exact model number stamped on your existing filter or unit — filters are rarely interchangeable across brands or even across a single brand's different product lines.
Do I need to test my water before choosing a filter?
It helps. See our Water Testing & Quality guide — knowing what's actually in your water (chlorine, hardness, specific contaminants) narrows down which filter type is worth buying.
