Is under sink water filter profitable to sell on Amazon United States?

The niche generates $2.8M/yr across 18 tracked products. 2 of 2 products launched in the last 360 days are still selling. 90-day search growth is +10.5%. Flapen's verdict: Skip it (43/100).

How competitive is the under sink water filter niche?

8 brands and 15 sellers compete. The top 5 products take 63% of clicks and top 5 brands hold 96% of demand.

What do buyers complain about in under sink water filter?

Top complaints mined from reviews: Leak-Proof, Filtration, Assembly/Installation. The return rate is 5.1% — above our launch gate.

When does demand for under sink water filter peak?

Demand is steady year-round — the busiest month runs 1.4× the quietest.

What does it cost to enter the under sink water filter niche?

Listings span $34.84–$422.62; the average listing price is $109.75 (sweet spot $15–$100). The average incumbent carries 5,289 reviews — the moat a new listing must climb.

under sink water filter

Skip it

Brand-locked demand (top 5 brands take 96% of clicks) — this niche doesn't clear our bar today.

Market size

Incredible$2.8M

$2.8M/yr · 986K searches

Avg price

Good$109.75

avg listing price — sweet spot $15–$100

Quality gap

Okay4.5★

avg incumbent rating — lower means beatable quality

Growth

Okay+10.5%

90-day search growth — must beat 0% to launch

Competition

Okay63%

top-5 click share — leaders hold, buyers still browse

Conversion

Okay2.6%

search→purchase rate — share of searches ending in a sale

Returns

Bad5.1%

return rate — above 5% kills the launch gate

Review moat

Bad5,288.72

avg incumbent reviews — the moat a new listing must climb

Price range

Bad$34.84–$422.62

cheapest to priciest tracked listing — scored on the share inside $15–$100

Brand share

Bad96%

top-5 brand share — brand-locked demand

Signals High Returns High Price

According to Flapen's Amazon United States niche tracking, under sink water filter is a $2.8M/yr Amazon United States market (986K searches/yr). The top 5 brands hold 96% of demand. Verdict: Skip it — 43/100.

Data updated Jul 28, 2026 · scored weekly · How we score niches

under sink water filter market data

Units sold / yr: 20K–25K; avg 1,250–1,500/product
Revenue / yr: $2.2M–$2.7M; units × avg price
Conversion rate: 2.6%
Avg BSR: #34
Page quality: 0%
Prime: 100%
Sponsored: 100%
Out of stock: 0.0%
Avg brand age: 65 months
Avg seller age: 148 days

Competition & brand share

The top 5 products take 63% of clicks — established leaders, but buyers still shop beyond them.

Brands

8 falling

Sellers

Top-5 brand share

96%

Top 20: 100%

Top-5 click share

63%

Top 20: 100%

Open market

Waterdrop74%
iSpring8%
ICEPURE7%
CuZn5%
Amazon Basics2%
PUREPLUS2%
Open — no brand owns it (2 brands, 3%)

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — +10.5% search growth over the last 90 days.

No pronounced peak months · busiest ÷ quietest = 1.4×

Open Trend

Top under sink water filter search terms

under sink water filter410K/yr -1.0%2.0% conv.
under sink water filter system91K/yr +173.0%1.6% conv.
undersink water filter systems79K/yr -1.8%1.7% conv.
under sink water filtration system107K/yr -38.3%1.5% conv.
water filter under sink61K/yr +11.8%1.9% conv.
under sink filter34K/yr +6.2%2.0% conv.
under the sink water filter system28K/yr -0.4%1.5% conv.
under the sink water filter23K/yr +13.8%1.7% conv.
undersink water filter20K/yr +27.1%1.8% conv.
hydroviv under sink water filter14K/yr +53.3%0.9% conv.

All search terms

Top under sink water filter products on Amazon

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 18 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Waterdrop 10UA Under Sink Water Filter System NSF/ANSI 42 Certified 1 Year

Waterdrop$42.054.6★13,883 rev

Waterdrop TSA 8 Layer Under Sink Water Filter System NSF/ANSI 42 Certified

Waterdrop$97.394.5★2,475 rev

Waterdrop 15UA Under Sink Water Filter System 19000 Gallons 2 Years

Waterdrop$54.614.5★8,568 rev

Waterdrop TSU 0.01 Micron Ultra Filtration Under Sink Water Filter System

Waterdrop$136.714.5★3,390 rev

iSpring RCC7AK-BN NSF Certified 75 GPD Alkaline 6-Stage Reverse Osmosis System pH+ Remineralization RO Water Filter System Under Sink Patented Top-Mounted Faucet Design for Easy Installation

iSpring$209.734.6★15,066 rev

Newest

by launch date

AQUALTRA USF01-BK Under Sink Water Filter System 12K Gal NSF/ANSI/CAN 372 Certified Reduces PFOA PFOS Chlorine Lead Mercury Chloramine Fluoride Microplastics Particles Bad Taste & Odor

AQUALTRA$39.4146 rev

4mo ago

Amazon Basics Under Sink Water Filter System NSF/ANSI 42 & 372 Certified Easy Twist-and-Lock Design 11 000 Gallons 1 Year Service Life White

Amazon Basics$34.84180 rev

11mo ago

Waterdrop UL12A Under Sink Water Filter Upgraded for 10UA Time Reminder

Waterdrop$50.0413,883 rev

1y ago

Waterdrop WD-TSA-UF 0.01 m Ultra Filtration Under Sink Water Filter System

Waterdrop$116.401,447 rev

2y ago

Waterdrop UA-5Y 5-Year Under Sink Water Filter System Ultra Long Life

Waterdrop$97.668,568 rev

2y ago

What buyers say about under sink water filter

What buyers praise and complain about, mined from review topics.

What buyers love

Assembly/Installation28%

“Easy assembly”

Filtration17%

“Excellent Filter”

Quality-Overall11%

“The build quality feels solid”

Value For Money6%

“Great Value”

Ease Of Use3%

“makes it easy to remove”

Ease Of Cleaning2%

“is easy to clean”

Instructions/User Manual/Troubleshooting2%

“Easy to follow instructions”

Water Flow2%

“The water flow is great”

Advertised Vs Actual Product2%

“As Advertised”

Efficiency2%

“Works great and clears the water”

What buyers complain about

Leak-Proof18%

“Leaking”

Filtration14%

“Doesn't filter well”

Assembly/Installation8%

“This is not an easy install”

Value For Money3%

“Did not purchase too expensive”

Quality-Overall3%

“the quality control needs improvement”

Durability2%

“Stopped working after a week”

Noise Level2%

“Very Noisy”

Smell2%

“smells like a dead animal”

Size-Overall2%

“Short by an entire inch”

Water Resistance2%

“The water is dripping from underneath the machine itself”

Top return reasons

Size-Overall31%

Filtration15%

Compatibility-Overall9%

Assembly/Installation9%

Value For Money7%

Leak-Proof6%

Advertised Vs Actual Product4%

Functionality-Overall4%

Connectivity-Overall3%

Defective Material/Parts3%

Common questions

Is under sink water filter profitable to sell on Amazon United States?: The niche generates $2.8M/yr across 18 tracked products. 2 of 2 products launched in the last 360 days are still selling. 90-day search growth is +10.5%. Flapen's verdict: Skip it (43/100).
How competitive is the under sink water filter niche?: 8 brands and 15 sellers compete. The top 5 products take 63% of clicks and top 5 brands hold 96% of demand.
What do buyers complain about in under sink water filter?: Top complaints mined from reviews: Leak-Proof, Filtration, Assembly/Installation. The return rate is 5.1% — above our launch gate.
When does demand for under sink water filter peak?: Demand is steady year-round — the busiest month runs 1.4× the quietest.
What does it cost to enter the under sink water filter niche?: Listings span $34.84–$422.62; the average listing price is $109.75 (sweet spot $15–$100). The average incumbent carries 5,289 reviews — the moat a new listing must climb.