Water Filters · Head-to-head
Culligan US-EZ-4 vs Waterdrop WD-G3P800-W
Best for Maximum PFAS Removal (Reverse Osmosis)
Waterdrop WD-G3P800-W
7.4/10
$759.00 at Amazon
Check price at Amazon
The short answer
Culligan US-EZ-4 comes out ahead overall with 7.8/10 against 7.4/10 for the Waterdrop WD-G3P800-W. Culligan US-EZ-4 is stronger on value, installation & cabinet fit, health, materials & sustainability and reliability & support. Waterdrop WD-G3P800-W is stronger on pfas reduction evidence, other contaminant coverage and flow & daily convenience. At current verified prices, the Culligan US-EZ-4 costs about $646.03 less.
- Choose the Culligan US-EZ-4 if: Budget buyers who want a PFAS-certified filter with its own faucet for under $100 and cheap yearly cartridges.
- Choose the Waterdrop WD-G3P800-W if: Households with known high PFAS or TDS that want the best-documented broad removal and have an outlet and drain under the sink.
Scores by criterion
| Criterion | Culligan US-EZ-4 | Waterdrop WD-G3P800-W |
|---|---|---|
| PFAS reduction evidence | 8.0IAPMO NSF 53 PFOA/PFOS certification, on the WA DOH list; no independent lab test. | 9.0NSF 53 PFOA/PFOS certification plus an independent 14-compound panel, though only one panel. |
| Other contaminant coverage | 6.542/53/401 claims incl. lead and chloramine; single-stage carbon. | 9.0RO plus NSF 58: TDS, fluoride, arsenic and nitrate on top of 42/53. |
| Value | 9.5About $98 upfront and about $108 a year in cartridges. | 5.0$849 upfront; about $145 a year in filters. |
| Installation & cabinet fit | 7.5One canister, no power or drain; dedicated faucet may need a hole. | 5.0Needs an outlet, a drain saddle and a faucet hole. |
| Flow & daily convenience | 6.00.5 gpm; twist-off cartridge every 500 gal/6 months. | 8.0Rated 800 GPD on demand with a filter-life faucet; no measured flow figure. |
| Health, materials & sustainability | 7.5No wastewater or power; minerals kept; no BPA disclosure found. | 7.0NSF 372, efficient 3:1, but uses power; pH fell to 6.3 without remineralization. |
| Reliability & support | 7.52-year limited warranty; install errors cause leaks. | 6.01-year warranty; many bundle ASINs. |
Specifications
| Spec | Culligan US-EZ-4 | Waterdrop WD-G3P800-W |
|---|---|---|
| Filter type | Carbon block, single cartridge | Tankless reverse osmosis (with UV LED) |
| 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) | IAPMO R&T to NSF/ANSI 53 for PFOA/PFOS; also NSF/ANSI 42, 58, 372 |
| Third-party certified for PFAS | Yes | Yes |
| Filtration stages | 1 | — |
| Filter capacity (primary cartridge) | 500 gal | — |
| Rated filter life | 6 months | — |
| Rated flow rate | 0.5 gpm | — |
| Est. annual filter cost | 108 USD | 145 USD |
| Pure-to-drain ratio (RO) | None (no RO) | 3:1 |
| Needs electrical outlet | No | Yes |
| Uses dedicated faucet (drilling may be needed) | Yes | Yes |
Culligan US-EZ-4
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
The best value for a certified carbon filter, driven by low running costs rather than a big upfront discount.
Full Culligan US-EZ-4 review →Waterdrop WD-G3P800-W
Pros
- Certified for PFOA/PFOS and lab-tested across 14 PFAS compounds
- Also certified to NSF/ANSI 42, 58 and 372
- Tankless design
- Broad RO coverage including TDS
Cons
- Premium price; street prices vary widely, so confirm you're buying the base unit
- Needs an outlet, a drain connection and a dedicated faucet
- Without the optional remineralization cartridge, Water Filter Guru measured pH dropping from 7.3 to 6.3
- 1-year warranty
The strongest choice for known high PFAS or high TDS. For everyone else, it is more system than you need.
Full Waterdrop WD-G3P800-W review →Both products are part of our guide The Best Under-Sink Filters for PFAS of 2026, where you can see every pick, how we score and current prices from each retailer.