cistern fill valve
Skip itBrand-locked demand (top 5 brands take 96% of clicks) — this niche doesn't clear our bar today.
Conversion
Great7.3%search→purchase rate — share of searches ending in a sale
Returns
Great2.0%return rate — above 5% kills the launch gate
Review moat
Good541.73avg incumbent reviews — the moat a new listing must climb
Quality gap
Good4.5★avg incumbent rating — lower means beatable quality
Avg price
Okay£9.84avg listing price — sweet spot $15–$100
Growth
Okay+2.4%90-day search growth — must beat 0% to launch
Market size
Bad£91K£91K/yr · 127K searches
Competition
Bad73%top-5 click share — a locked-up shelf
Price range
Bad£4.23–£16.19cheapest to priciest tracked listing — scored on the share inside $15–$100
Brand share
Bad96%top-5 brand share — brand-locked demand
According to Flapen's Amazon United Kingdom niche tracking, cistern fill valve is a £91K/yr Amazon United Kingdom market (127K searches/yr). The top 5 brands hold 96% of demand. Verdict: Skip it — 38/100.
Data updated Jul 21, 2026 · scored weekly · How we score niches
cistern fill valve market data
- Units sold / yr
- 8K–10K
- avg 250–500/product
- Revenue / yr
- £79K–£98K
- units × avg price
- Conversion rate
- 7.3%
- Avg BSR
- #41
- Page quality
- 0%
- Prime
- 93%
- Sponsored
- 87%
- Out of stock
- 1.1%
- Avg brand age
- 39 months
- Avg seller age
- 166 days
Competition & brand share
The top 5 products capture 73% of clicks — a locked-up shelf that new listings rarely crack.Brands
7 falling
Sellers
53
Top-5 brand share
96%
Top 20: 100%
Top-5 click share
73%
Top 20: 100%
Open market
2%
- Fluidmaster33%
- VeeBath31%
- Fzosinou14%
- PlumbEZ10%
- Hulthor8%
- Taps2Traps2%
- Open — no brand owns it (1 brand, 2%)
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — +2.4% search growth over the last 90 days.No pronounced peak months · busiest ÷ quietest = 1.4×
Top cistern fill valve search terms
- toilet fill valve24K/yr
- cistern fill valve15K/yr
- fluidmaster flush valve12K/yr
- toilet cistern fill valve13K/yr
- bottom entry toilet fill valve8K/yr
- toilet inlet valve7K/yr
- toilet fill valve bottom entry8K/yr
- toilet float valve7K/yr
- toilet inlet valve bottom entry7K/yr
- fluidmaster6K/yr
Top cistern fill valve 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.
All 15 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
VeeBath Toilet Inlet Valve Bottom Entry Inlet Float Valve 1/2 inch
VeeBath£8.554.5★3,079 rev
Fluidmaster PRO45B Fill Valve with Brass Shank - Black
Fluidmaster£14.704.6★1,635 rev
Toilet Flush System Replacement Adjustable Bottom Entry Toilet Fill Valve High Pressure Cistern Fill Valve - Prevents Backflow for Home Bathroom Tank Maintenance Water Saving
Fzosinou£8.304.4★13 rev
Hulthor Bottom Entry Toilet Fill Valve Toilet Inlet Valve Replacement 1/2 UK Brass Thread Adjustable 8-12 Compact Cistern Float
Hulthor£12.374.8★85 rev
PlumbEZ Adjustable Bottom Entry Toilet Fill Valve with UK Brass Threads - Cistern Fill Valve with Delayed Fill Quiet Operation Telescopic Height 8-12 & Water Saving Filter - Brass Threads
PlumbEZ£11.894.9★55 rev
Newest
by launch dateToilet Flush System Replacement Adjustable Bottom Entry Toilet Fill Valve High Pressure Cistern Fill Valve - Prevents Backflow for Home Bathroom Tank Maintenance Water Saving
Fzosinou£8.3013 rev
PlumbEZ Universal Side Entry Toilet Cistern Fill Valve with Adjustable Float Arm - 1/2 Toilet Inlet Valve Side Entry Fill Ball Valve with Float
PlumbEZ£8.5548 rev
PlumbEZ Toilet Cistern Fill Valve Bottom Entry with Float - 1/2 Toilet Fill Valve with Adjustable Arm | Ballcock for Toilet Cistern with Ball Float
PlumbEZ£9.8635 rev
Hulthor Bottom Entry Toilet Fill Valve Toilet Inlet Valve Replacement 1/2 UK Brass Thread Adjustable 8-12 Compact Cistern Float
Hulthor£12.3785 rev
PlumbEZ Adjustable Bottom Entry Toilet Fill Valve with UK Brass Threads - Cistern Fill Valve with Delayed Fill Quiet Operation Telescopic Height 8-12 & Water Saving Filter - Brass Threads
PlumbEZ£11.8955 rev
Trending
90-day click momentumToilet Flush System Replacement Adjustable Bottom Entry Toilet Fill Valve High Pressure Cistern Fill Valve - Prevents Backflow for Home Bathroom Tank Maintenance Water Saving
Fzosinou£8.304.4★
W.C. Fill Valve Bottom Entry
Fluidmaster£5.614.3★
W.C. Fill Valve Side Entry
Fluidmaster£4.384.3★
Fluidmaster PRO550LC Pro Button Cable Dual Flush Valve 550mm Long Dual Flush Cable Valve for Concealed Cisterns Top or Front Push Buttons 1 & 2 Outlet Fit White
Fluidmaster£16.194.7★
PlumbEZ Adjustable Bottom Entry Toilet Fill Valve with UK Brass Threads - Cistern Fill Valve with Delayed Fill Quiet Operation Telescopic Height 8-12 & Water Saving Filter - Brass Threads
PlumbEZ£11.894.9★
What buyers say about cistern fill valve
What buyers praise and complain about, mined from review topics.What buyers love
“Easy fit”
“Excellent product”
“Easy to install and set up”
“Perfect works as it should”
“Decent value”
“Easy to use”
“adjustable”
“does the job perfectly”
“Hopefully, there is no leakage”
“is much quieter”
What buyers complain about
“It was smaller than the original broken one too”
“Leaked”
“does seem noisy compared to my previous top fill one”
“Bad quality”
“as none of them seem to last more than a couple of years”
“Product arrived broken”
“Does not work”
“thicker than original”
“Sadly this item will not stop letting in the water so I have to manually turn the water off”
“The only reason Im giving 4 stars instead of 5 is that the plastic feels a little lightweight”
Top return reasons
Common questions
- Is cistern fill valve profitable to sell on Amazon United Kingdom?
- The niche generates £91K/yr across 15 tracked products. 1 of 1 products launched in the last 360 days are still selling. 90-day search growth is +2.4%. Flapen's verdict: Skip it (38/100).
- How competitive is the cistern fill valve niche?
- 7 brands and 53 sellers compete. The top 5 products take 73% of clicks and top 5 brands hold 96% of demand.
- What do buyers complain about in cistern fill valve?
- Top complaints mined from reviews: Size-Overall, Leak-Proof, Noise Level. The return rate is 2.0%.
- When does demand for cistern fill valve peak?
- Demand is steady year-round — the busiest month runs 1.4× the quietest.
- What does it cost to enter the cistern fill valve niche?
- Listings span £4.23–£16.19; the average listing price is £9.84 (sweet spot $15–$100). The average incumbent carries 542 reviews — the moat a new listing must climb.