Water Filtration Buying Guide

The right filter depends on what is in your water. Start with your contaminant, match to the certification that removes it, then choose a format for your kitchen and budget.

Choose by contaminant

Lead

NSF/ANSI 53 certified carbon block filters reduce lead below 10 ppb. Pitchers like Brita Elite carry this cert. Under-sink carbon blocks are more consistent long-term.

PFAS

NSF P473 or reverse osmosis. Activated carbon alone misses short-chain PFAS. RO rejects 90-99% of PFAS compounds.

Fluoride

Standard carbon does not remove fluoride. Use reverse osmosis (90-95% removal), bone char, or activated alumina.

Chlorine / taste

Any NSF 42 carbon filter. Even a $20 pitcher handles it.

Choose by budget

$35-$50 (pitcher): NSF 53 for lead, NSF 42 for chlorine. Replace every 2 months. Best for renters.

$80-$150 (countertop/gravity): Clearly Filtered ($80, NSF P473) or Big Berkey ($150). Better contact time.

$150-$300 (under-sink carbon): Multi-stage, dedicated faucet, 6-12 month filter life.

$300-$449 (under-sink RO): Removes virtually everything. Wastes 2-3 gal per gallon. Add remineralization.

Choose by setup

Pitcher: no install, portable, cheapest. Slow, small capacity, frequent replacement.

Countertop: faucet-connect or gravity-fed. No plumbing mod. Good for renters.

Under-sink: permanent, invisible, best long-term value. Needs plumbing skill or $100-$200 install.

Whole-house: $1,000-$3,000+ installed. Necessary if concerned about shower/inhalation exposure.

Decision flowchart

1. Test your water first -- know your contaminants before buying.

2. Lead only? NSF 53 pitcher ($35-$50).

3. PFAS or fluoride? RO ($300-$449) or specialty media.

4. Renter? Pitcher or countertop.

5. Homeowner wanting comprehensive removal? Under-sink RO.