Waterdrop WHF21-PG
#1 in CartridgeFull review
A low cost starter system for chlorinated city water in a small home.
Amazon $106.98$106.98
3.4/5
A low cost first whole-house filter for city water with chlorine taste. Expect to change filters several times a year.
- $0.90 per 1,000 galRunning cost
- 50,000 gallonsCapacity
- 15 gpmFlow
Check price at Amazon$155.99
Price checked November 2, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Cheap to buy and cheap to run, with a filter set that costs under $50
- Takes out sediment, chlorine taste and odor at every tap
- Standard 10 x 4.5 in housings take filters from many brands
Cons
- Small 10 in housings need new filters every few months in a busy house
- Tested to NSF/ANSI 42, not certified
- Does not claim to reduce chloramine
The iSpring WGB Series family
Every iSpring WGB Series model we rank, smallest first. Ratings compare each against its own build.
| Model | Running cost | Rating | Price |
|---|---|---|---|
| iSpring WGB21B (this one) | $0.90 per 1,000 gal | 3.4/5 | $155.99 |
| iSpring WGB21B-PB | $2.44 per 1,000 gal | 2.6/5 | $230.99 |
| iSpring WGB22B | $0.83 per 1,000 gal | 3.1/5 | $286.70 |
| iSpring WGB32B | $1.15 per 1,000 gal | 2.9/5 | $420 |
| iSpring WGB32B-KSNC | - | 2.8/5 | $639.99 |
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its build. How we rank explains each one.
Specifications
| Model number | WGB21B |
|---|---|
| Filtration | |
| Capacity | 50,000 gallons |
| Replacement filters or media | $45.11 |
| Running cost | $0.90 per 1,000 gal |
| Stages | 2 |
| Tested to (not certified) | NSF/ANSI 42 |
| Chloramine | No |
| PFAS | No |
| Build | |
| Flow | 15 gpm |
| Ports | 1 in |
| UV stage | No |
| Warranty | 1 year |
Alternatives in this build
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
3M Aqua-Pure AP903
#4 in CartridgeFull review
A certified, low mess choice for city water with chlorine, for owners who would rather pay more per cartridge than handle filters.
Amazon $422.99$422.99
Compare
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