Culligan US-EZ-4 vs Aquasana AQ-5200
Bottom line
Both are excellent, genuinely certified picks - you are not making a mistake either way. The Culligan's NSF/ANSI 401 and PFAS certification gives it a slightly wider net, so it edges ahead on breadth. Compare cost per gallon against how much water you actually filter before you decide.
This is a happy problem: both are among the best-certified under-sink filters we score, so you are choosing between two good options, not avoiding a bad one. The Culligan is IAPMO-certified to NSF/ANSI 42, 53, and 401 - the last of which covers harder-to-catch contaminants like pharmaceuticals - including PFOA/PFOS. The Aquasana is certified for lead, PFAS, and chlorine. It comes down to how wide a certified net you want and what each costs to run.
| 10 certified / 11 marketed | Certified vs marketed contaminants | 12 certified / 12 marketed |
| 9.0 | Verified Contaminant Reduction35% | 9.0 |
| 5.0 | Total Cost of Ownership25% | 2.5 |
| 8.0 | Certification Independence15% | 10.0 |
| 8.0 | Capacity & Flow Fit15% | 8.0 |
| 7.0 | Practical Fit10% | 7.0 |
FAQ
- Is the Culligan US-EZ-4 Under-Sink better than the Aquasana AQ-5200 Under-Sink?
- In our scoring the Culligan US-EZ-4 Under-Sink rates 7.5/10 and the Aquasana AQ-5200 Under-Sink 7.2/10. Both are excellent, genuinely certified picks - you are not making a mistake either way. The Culligan's NSF/ANSI 401 and PFAS certification gives it a slightly wider net, so it edges ahead on breadth. Compare cost per gallon against how much water you actually filter before you decide.
- Are both certified for PFAS?
- Yes - and that puts them ahead of most of the field. The Culligan is certified for PFOA/PFOS under NSF/ANSI 401, and the Aquasana is certified for PFOA/PFOS as well. Both certifications you can look up, unlike the many 'tested to' competitors whose claims we cannot verify.