Claim Method
The filter, cartridge, claim, and receipt all have to line up.
Filter Report scores water filters by certification evidence, buyer fit, maintenance economics, installation burden, and whether the claim can be stated without overpromising.
What We Record
The receipt ledger
Exact model and element
Record the sold system, model number, replacement cartridge, bundle caveats, and compatibility notes separately.
A certification for one cartridge or system cannot be copied to every related SKU.
Certifier and standard
Separate NSF, WQA, IAPMO, manufacturer performance sheets, third-party lab reports, and marketplace copy.
Certified, tested, and claimed are different evidence classes.
Service and cost
Track service cycle, replacement element, estimated annual filter spend, and compatible-cartridge risks.
A filter that is not replaced on time may not perform as claimed.
Install burden
Flag faucet fit, drilling, drain lines, electricity, tank footprint, leak checks, and renter constraints.
The best receipt does not help if the buyer cannot install or maintain the product.
Score Formula
A source-audit rating
Ratings compare products inside this launch shortlist. They are not lab-test scores and can move when certification status, price, or replacement availability changes.
30%
Evidence strength
Exact certifier receipt, standard, contaminant, model, and cartridge match.
20%
Buyer fit
How cleanly the filter maps to lead/PFAS concern, taste, renter constraints, RO, or low-maintenance use.
20%
Maintenance economics
Replacement cost, service cycle, element availability, and generic-cartridge risk.
15%
Installation friction
Faucet fit, under-sink space, drain line, power, tank, drilling, and leak risk.
15%
Claim restraint
Whether the product can be described without unsafe or unsupported safety language.
Safety Boundary
A product page cannot test your water.
Use your Consumer Confidence Report for public water, a state-certified lab for private wells when needed, and local public-health guidance for advisories or vulnerable-user contexts.
- A filter recommendation is not a water test.
- Certified to reduce does not mean removes every contaminant or all PFAS.
- Private wells, boil-water notices, and immune-risk contexts need qualified local guidance.
- Affiliate links never change rating or evidence tier.
Start with the shortlist.
Compare filters by evidence tier, certifier, replacement cost, service cycle, and installation burden.
Compare water filters