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Whole-House vs Point-of-Use Water Filtration

Whole-house (POE) filters treat all water entering your home. Point-of-use (POU) filters treat water at a single tap. Different problems, different solutions.

Removes

  • • Whole-house: chlorine, chloramine, sediment, scale, taste/odor at every tap
  • • Point-of-use (carbon under-sink): chlorine, taste/odor, VOCs, some DBPs
  • • Point-of-use (RO under-sink): lead, PFAS, fluoride, nitrates, arsenic, chromium-6
  • • Point-of-use (pitcher): lead (NSF 53 certified only), chlorine, taste/odor

Does Not Remove

  • • Whole-house carbon: lead, PFAS, nitrates, fluoride (require point-of-use RO)
  • • Whole-house sediment: any dissolved contaminants
  • • Point-of-use carbon: nitrates, fluoride, most dissolved inorganics
  • • UV (either placement): any dissolved chemical contaminants

POE vs POU: Two Systems Solving Two Different Problems

The decision between whole-house (point-of-entry, POE) and point-of-use (POU) filtration comes down to what you are trying to protect: your appliances and water comfort throughout the home, or your health at the point of consumption.

Whole-house filters treat water at the main entry to your home. Every gallon that flows to any fixture passes through the system — shower, toilet, dishwasher, garden hose. The volume is high (100-300 gallons/day for a family of 4), so the filter media must work at high flow rates. High flow rate means less contact time with the media, which limits depth of filtration. Under-sink filters treat only the 2-4 gallons per day your family actually drinks — at 0.5-1.5 GPM, with far more media contact time, enabling certified removal of health contaminants.

What Each System Accomplishes

Whole-House (POE)

✓ Chlorine removal at all taps
Better tasting shower water, cooking water, laundry
✓ Sediment removal
Protects water heaters, dishwashers, and washing machines
✓ Chloramine reduction (catalytic carbon)
Reduces skin and respiratory irritation throughout home
✓ Iron and hydrogen sulfide removal
KDF-85 media targets well water iron and rotten egg odor
✓ Whole-home VOC reduction
Carbon reduces shower water off-gassing
✗ Does not provide
NSF 53 lead reduction, NSF P473 PFAS reduction, nitrate removal, fluoride removal

Under-Sink (POU)

✓ NSF 53 lead reduction
99%+ removal certified for drinking water
✓ NSF P473 PFAS reduction
Only certified technology for PFAS removal (Clearly Filtered)
✓ Nitrate removal (RO)
88-92% nitrate reduction at the kitchen tap
✓ Fluoride reduction (RO)
85-95% fluoride removal
✓ NSF 401 emerging contaminant reduction
Pharmaceuticals, microplastics, personal care products
✗ Does not provide
Shower water improvement, appliance protection, whole-home treatment

Decision Framework: What to Buy First

Health contaminants detected (lead, PFAS, nitrates)

Action: POU first — always
Recommendation: Aquasana AQ-5300+ ($149) for lead/chloramine; AquaTru ($349) or Clearly Filtered under-sink ($395) for PFAS

Only chlorine taste, skin issues, appliance scale

Action: POE whole-house filter
Recommendation: SpringWell CF1 ($869) for chloramine-heavy city water; Aquasana Rhino ($999) for broad city water treatment

Both health concerns AND chlorine/comfort concerns

Action: POU first, add POE when budget allows
Recommendation: AQ-5300+ under-sink + SpringWell CF1 when ready ($2,000-$2,500 combined 5-year)

Most Households: Start With Under-Sink, Add Whole-House Later

The under-sink filter protects your health at the point you consume water. The whole-house filter improves comfort and appliance longevity throughout your home. If you can afford only one: start with the under-sink system that addresses your specific water test results. A $149 AQ-5300+ provides more health protection per dollar than any whole-house system. Add the whole-house filter when budget and priority allow.

Top Products Using This Technology

9.5
Pitcher

Tap Score Essential City Water Test

aquasana

$179

  • ✓EPA-certified lab
  • ✓Tests 111 contaminants
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9.5
Pitcher

Tap Score Well Water Test

aquasana

$239

  • ✓EPA-certified lab
  • ✓Tests 130 contaminants specific to well water
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9.2
Pitcher
Clearly Filtered Water Pitcher

Clearly Filtered Water Pitcher

clearly filtered

$90+ $140/yr

  • ✓NSF P473 certified — removes 99.9% of PFAS
  • ✓Removes fluoride (unusual for a pitcher)
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9.1
Whole-House

SpringWell CF1 Whole-House Carbon Filter

springwell

$1,197

  • ✓1 million gallon capacity
  • ✓9 GPM flow rate — no pressure loss
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Frequently Asked Questions