Waterdrop WHF3T-PG
#3 in CartridgeFull review
A lower priced three stage big blue system for city water. Running cost is hard to judge without a gallon rating.
Amazon $269.99$269.99
The Waterdrop WHF3T-PG is the better whole-house water filter overall, rated 3.2 to 2.6. The Waterdrop WHF3T-PG leads on certification. The iSpring WGB21B-PB wins on price. The iSpring WGB21B-PB costs $39 less ($230.99 vs $269.99).
iSpring WGB21B-PB
#11 in CartridgeFull review
For homes worried about lead pipes or with chloramine treated water. The lead claim is not certified, so test the water if lead is the main concern.
Amazon $230.99$230.99
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Waterdrop WHF3T-PG for certification (tested to NSF/ANSI 42, not certified vs no certification in a public listing, no tested to claim).
- Choose the iSpring WGB21B-PB for price ($230.99 vs $269.99).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every cartridge whole-house water filter; a clear win is highlighted. How we rank explains each one.
| Factor weight | Waterdrop WHF3T-PG | iSpring WGB21B-PB |
|---|---|---|
| Overall rating | 3.2/5 | 2.6/5 |
| Running cost 25% | 50 filter cost or capacity not published (neutral score used) | 8 $2.44 per 1,000 gallons ($121.99 every 50,000 gallons) |
| Certification 25% | 30 tested to NSF/ANSI 42, not certified | 0 no certification in a public listing, no tested to claim |
| Flow 15% | 100 15 gpm service flow | 100 15 gpm service flow |
| Price 20% | 65 $269.99 | 74 $230.99 |
| Warranty 15% | 0 warranty not published, scored as none | 0 1-year warranty |
Specifications
| Waterdrop WHF3T-PG | iSpring WGB21B-PB | |
|---|---|---|
| Filtration | ||
| Capacity | - | 50,000 gallons |
| Replacement filters or media | - | $121.99 |
| Running cost | - | $2.44 per 1,000 gal |
| Stages | 3 | 2 |
| Tested to (not certified) | NSF/ANSI 42 | - |
| Chloramine | No | Yes |
| PFAS | No | No |
| Build | ||
| Flow | 15 gpm | 15 gpm |
| Ports | 1 in | 1 in |
| UV stage | No | No |
| Warranty | - | 1 year |