Water Filters

Culligan US-EZ-4

Name: Culligan US-EZ-4
Brand: Culligan

#3 · Best Value

7.8 /10 Our score

Lowest verified price $112.97 Amazon

Our verdict

The best value for a certified carbon filter, driven by low running costs rather than a big upfront discount.

Pros

IAPMO-certified for PFOA/PFOS, plus NSF/ANSI 42 and 401
Lowest annual cartridge cost of the certified picks
2-year warranty
On the Washington State DOH PFAS filter list

Cons

Single stage with 0.5 gpm flow
Install errors can cause leaks
Amazon price is from a third-party seller
Check the box for the PFOA/PFOS claim, as some documents omit it

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Last reviewed October 25, 2026

Review

What to know about Culligan US-EZ-4

A single twist-change cartridge under-sink filter with a dedicated faucet, rated 500 gallons/6 months at 0.5 gpm. IAPMO-certified to NSF/ANSI 53 for PFOA/PFOS (>95.8%) plus 42 and 401, with a 2-year warranty. The cheapest PFAS-certified under-sink unit here, at about $98 upfront and about $108 a year.

Editorial notes

Why it stands out

Why we like it

Culligan's spec sheet lists IAPMO R&T certification to NSF/ANSI 53 for PFOA/PFOS (above 95.8%) plus NSF/ANSI 42 and 401. The Washington State Department of Health's PFAS filter list links to it. Culligan's own store lists the unit at roughly $98, while the Amazon listing, from a third-party seller, is a bit higher, close to the AQ-5200.

The real saving is in the cartridges, about $108 a year, the lowest of any certified option here. The 2-year warranty is longer than most rivals offer.

What to know

Skip it if you want independent lab results or an editor-style recommendation. Its main review mention is a dated 2022 Good Housekeeping pick.

Performance

Score breakdown

PFAS reduction evidence

Strength of proof that the system cuts PFAS: a current NSF/ANSI 53/58 PFOA/PFOS or total-PFAS certification (NSF, WQA or IAPMO) and/or independent lab results (TechGearLab/Tap Score, Quality Water Lab). Certified plus lab-verified scores highest; marketing-only claims score lowest.

8.0

IAPMO NSF 53 PFOA/PFOS certification, on the WA DOH list; no independent lab test.

Other contaminant coverage

Certified or lab-verified reduction of lead, chlorine/chloramine, VOCs, pharmaceuticals (NSF 401), microplastics, and for RO, TDS, fluoride, nitrate and arsenic.

6.5

42/53/401 claims incl. lead and chloramine; single-stage carbon.

Value

Upfront price plus annual filter cost per gallon, judged against the protection delivered.

9.5

About $98 upfront and about $108 a year in cartridges.

Installation & cabinet fit

DIY difficulty, whether it needs a drilled faucet hole, a drain saddle or an electrical outlet, renter-friendliness, and under-sink footprint (tank vs tankless).

7.5

One canister, no power or drain; dedicated faucet may need a hole.

Flow & daily convenience

Flow rate or production speed, filter-change ease, and filter-life reminders.

6.0

0.5 gpm; twist-off cartridge every 500 gal/6 months.

Health, materials & sustainability

Lead-free component certification (NSF 372), BPA disclosures, wastewater ratio, energy use, effects on pH and minerals, and any media leaching found in lab tests.

7.5

No wastewater or power; minerals kept; no BPA disclosure found.

Reliability & support

Leak reports, warranty length, availability of replacement parts and filters.

7.5

2-year limited warranty; install errors cause leaks.

Specifications

Culligan US-EZ-4 specs

Design

Filter type: Carbon block, single cartridge
Filtration stages: 1

PFAS

PFAS certification (as stated by maker): IAPMO R&T to NSF/ANSI 53 for PFOA/PFOS (>95.8%), plus 42 and 401 (Culligan spec sheet; Culligan store confirms IAPMO and PFOA/PFOS)
Third-party certified for PFAS: Yes

Maintenance

Filter capacity (primary cartridge): 500 gal
Rated filter life: 6 months
Est. annual filter cost: 108 USD

Performance

Rated flow rate: 0.5 gpm

Sustainability

Pure-to-drain ratio (RO): None (no RO)

Installation

Needs electrical outlet: No
Uses dedicated faucet (drilling may be needed): Yes

Shopping

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Disclosure: We may earn a commission when you purchase through links on this page. This does not affect our editorial rankings.

Prices and availability may change. The retailer's price and availability at checkout govern the transaction.

Retailer	Price	Availability
AmazonLowest	$112.97	In Stock	View deal

Lowest verified price $112.97

30-day low $92.96

90-day average $110.20

90-day low $92.96

Based on 9 retailer price observations captured during the last 90 days.

More coverage

Guides featuring Culligan US-EZ-4

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