---
title: "Stain Block — £44K/yr Amazon UK Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/uk/diy-tools/stain-block"
last_updated: "2026-07-31T07:59:07.621Z"
locale: en
meta:
description: "Niche score 40/100 · £44K/yr market · 43K searches/yr · £8.83 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 40/100 · £44K/yr market · 43K searches/yr · £8.83 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "Stain Block — £44K/yr Amazon UK Niche (2026) - Flapen"
---
# **stain block**
**Skip it**
Prices mostly outside the sweet spot ($4.40–$15.55) — this niche doesn't clear our bar today.
Market size 11Growth 10Conversion 94Competition 17Returns 96Price range 5Avg price 25Brand share 29Review moat 57Quality gap 82
**Returns**
**Incredible****0.8%**
return rate — above 5% kills the launch gate
**Conversion**
**Great****11.7%**
search→purchase rate — share of searches ending in a sale
**Quality gap**
**Great****4.2★**
avg incumbent rating — lower means beatable quality
**Review moat**
**Good****1,231.92**
avg incumbent reviews — the moat a new listing must climb
**Brand share**
**Okay****87%**
top-5 brand share — brands hold most of the demand
**Avg price**
**Okay****£8.83**
avg listing price — sweet spot $15–$100
**Competition**
**Bad****79%**
top-5 click share — a locked-up shelf
**Market size**
**Bad****£44K**
£44K/yr · 43K searches
**Growth**
**Bad****-29.4%**
90-day search growth — must beat 0% to launch
**Price range**
**Bad****£4.40–£15.55**
cheapest to priciest tracked listing — scored on the share inside $15–$100
According to Flapen's Amazon United Kingdom niche tracking, stain block is a £44K/yr Amazon United Kingdom market (43K searches/yr). The top 5 brands hold 87% of demand. Verdict: Skip it — 40/100.
Data updated Jul 22, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **stain block market data**
- **Units sold / yr**
- **6K–8K**
- avg 250–500/product
- **Revenue / yr**
- **£53K–£71K**
- units × avg price
- **Conversion rate**
- **11.7%**
- **Avg BSR**
- **#122**
- **Page quality**
- **0%**
- **Prime**
- **85%**
- **Sponsored**
- **69%**
- **Out of stock**
- **0.0%**
- **Avg brand age**
- **82 months**
- **Avg seller age**
- **182 days**
## **Competition & brand share**
The top 5 products capture 79% of clicks — a locked-up shelf that new listings rarely crack.
**Brands**
**10 **▲rising
**Sellers**
**73**
**Top-5 brand share**
**87%**
Top 20: 100%
**Top-5 click share**
**79%**
Top 20: 100%
**Open market**
**7%**
- Everbuild27% - Polar Specialist Coatings22% - Pro-Kleen22% - RUSTINS11% - Bartoline6% - Zinsser5% - Open — no brand owns it (4 brands, 7%)
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — -29.4% search growth over the last 90 days.
1K750Spike '25Black Friday '25Spike '26 seasonSepDecMarJunAugNovMarMay
No pronounced peak months · busiest ÷ quietest = 1.5×
[**Open Trend **](https://flapen.com/research/uk/diy-tools/stain-block/trend)
## **Top stain block search terms**
- **stain block**23K/yr-36.5%9.2% conv. - **stain blocker spray**16K/yr-19.9%14.9% conv. - **stain block spray**4K/yr-26.5%13.9% conv. [**All search terms **](https://flapen.com/research/uk/diy-tools/stain-block/search-terms)
## **Top stain block 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.
0%10%£4K20%£9K30%£13K40%£18K101001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 13 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**Everbuild Stain Block Highly Pigmented Easy to Use White 400ml**Everbuild**£6.51**4.4★4,385 rev](https://www.amazon.co.uk/dp/B00578300M) [2**Pro-Kleen Damp & Stain Block Spray Paint Primer White Matt 400ml - Covers Damp Mould Grease Nicotine & Rust Stains - for Walls & Ceilings - Leaves a Waterproof Barrier**Pro-Kleen**£6.71**4.3★439 rev](https://www.amazon.co.uk/dp/B0BZSS6L5W) [3**Polar Damp & Stain Block Spray - 500ml Matt White - Covers Damp Mould Grease Nicotine & Rust Stains - Anti Mould & Damp Proof Paint for Internal Walls & Ceilings - Dries in 10 Min Low Odour**Polar Specialist Coatings**£10.12**4.3★3,347 rev](https://www.amazon.co.uk/dp/B0953Q5YHG) [4**Rustins Stain Blocker & Multi-Surface Primer 250ml- Versatile All-Surface Primer for Blocking Stains and Sealing Porous Materials; Optimal for Walls Ceilings and Wood**RUSTINS**£6.37**4.3★2,532 rev](https://www.amazon.co.uk/dp/B01LO54KWI) [5**Polar Stain Block Spray - 1 x 400ml | Matt White | Prevents & Removes Stains Grease Water Marks & Rust on Internal Walls & Ceilings | Primer Spray for Wood Plastic Tiles & Painted Surfaces**Polar Specialist Coatings**£8.94**4.2★416 rev](https://www.amazon.co.uk/dp/B09QT6XVGP)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**Bartoline Stain Blocker Spray 400ml Matt Finish Blocks Mould Mildew Damp and Grease Stains Fast-Drying Primer or Topcoat for Walls Ceilings Plaster and Woodwork**Bartoline**£8.03**79 rev11mo ago](https://www.amazon.co.uk/dp/B0FKGWQQL2) [**SPRAYTEKK Damp & Stain Block Primer Spray | 500ml | Matt White | Anti-Mould Smoke & Stain Coverage | Interior Use on Plaster Cement Stone Wood & Brick (Matt White Pack Of 1)**SPRAYTEKK**£8.72**102 rev1y ago](https://www.amazon.co.uk/dp/B0F679BWK1) [**Pro-Kleen Damp & Stain Block Spray Paint Primer White Matt 400ml - Covers Damp Mould Grease Nicotine & Rust Stains - for Walls & Ceilings - Leaves a Waterproof Barrier**Pro-Kleen**£6.71**439 rev3y ago](https://www.amazon.co.uk/dp/B0BZSS6L5W) [**Pro-Kleen Stain Block Spray Paint Primer - Covers Mould Grease Nicotine & Rust Stains - for Walls & Ceilings - Leaves a Waterproof Barrier - White Matt (400ml)**Pro-Kleen**£6.64**184 rev3y ago](https://www.amazon.co.uk/dp/B0BZJQXP3K) [**Polar Stain Block Spray - 1 x 400ml | Matt White | Prevents & Removes Stains Grease Water Marks & Rust on Internal Walls & Ceilings | Primer Spray for Wood Plastic Tiles & Painted Surfaces**Polar Specialist Coatings**£8.94**416 rev4y ago](https://www.amazon.co.uk/dp/B09QT6XVGP)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**Zinsser ZINCSP400A 400 ml Cover Stain Primer/Finish Aerosol**Zinsser**£10.54**4.6★**▲ 110%**](https://www.amazon.co.uk/dp/B00A497CR6) [**Polar Stain Block Spray - 1 x 400ml | Matt White | Prevents & Removes Stains Grease Water Marks & Rust on Internal Walls & Ceilings | Primer Spray for Wood Plastic Tiles & Painted Surfaces**Polar Specialist Coatings**£8.94**4.2★**▲ 63%**](https://www.amazon.co.uk/dp/B09QT6XVGP) [**SPRAYTEKK Damp & Stain Block Primer Spray | 500ml | Matt White | Anti-Mould Smoke & Stain Coverage | Interior Use on Plaster Cement Stone Wood & Brick (Matt White Pack Of 1)**SPRAYTEKK**£8.72**4.0★**▲ 38%**](https://www.amazon.co.uk/dp/B0F679BWK1) [**Bartoline Stain Blocker Spray 400ml Matt Finish Blocks Mould Mildew Damp and Grease Stains Fast-Drying Primer or Topcoat for Walls Ceilings Plaster and Woodwork**Bartoline**£8.03**4.3★**▲ 21%**](https://www.amazon.co.uk/dp/B0FKGWQQL2) [**Polar Damp & Stain Block Spray - 500ml Matt White - Covers Damp Mould Grease Nicotine & Rust Stains - Anti Mould & Damp Proof Paint for Internal Walls & Ceilings - Dries in 10 Min Low Odour**Polar Specialist Coatings**£10.12**4.3★**▲ 19%**](https://www.amazon.co.uk/dp/B0953Q5YHG)
**~~View all trending →~~**
## **What buyers say about stain block**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Advertised Vs Actual Product**17%
*“Just what I needed”*
**Quality-Overall**16%
*“Excellent coverage”*
**Stain Resistance**9%
*“Covered the water stain completely”*
**Ease Of Use**7%
*“Easy to use”*
**Efficiency**6%
*“Does the job”*
**Paint Quality**6%
*“Good coating really”*
**Coverage**6%
*“Covers well”*
**Value For Money**5%
*“Good Value For Money”*
**Ease Of Cleaning**3%
*“I found a soft brush made it easier”*
**Spray/Flow**3%
*“Its very easy to apply — quick spray, decent coverage, and no complicated prep beyond the obvious cleaning”*
### **What buyers complain about **
**Paint Quality**14%
*“Stain cover Paint”*
**Smell**12%
*“It smells terrible”*
**Spray/Flow**11%
*“One of these cans will not spray at all”*
**Leak-Proof**6%
*“Water leak through ceiling”*
**Quality-Overall**4%
*“Poor quality”*
**Coverage**4%
*“The coverage is very poor”*
**Functionality-Overall**4%
*“Doesn't work”*
**Value For Money**3%
*“Waste of money”*
**Color**3%
*“There was a terrible water mafk which was dark yellow on my ceiling”*
**Advertised Vs Actual Product**3%
*“Doesnt do what it says on the tin”*
### **Top return reasons **
**Spray/Flow**28%
**Paint Quality**16%
**Functionality-Overall**14%
**Leak-Proof**10%
**Defective Material/Parts**5%
**Size-Overall**5%
**Advertised Vs Actual Product**5%
**Quality-Overall**4%
**Color**3%
**Value For Money**3%
## **Common questions**
- **Is stain block profitable to sell on Amazon United Kingdom?**
- The niche generates £44K/yr across 13 tracked products. 1 of 1 products launched in the last 360 days are still selling. 90-day search growth is -29.4%. Flapen's verdict: Skip it (40/100).
- **How competitive is the stain block niche?**
- 10 brands and 73 sellers compete. The top 5 products take 79% of clicks and top 5 brands hold 87% of demand.
- **What do buyers complain about in stain block?**
- Top complaints mined from reviews: Paint Quality, Smell, Spray/Flow. The return rate is 0.8%.
- **When does demand for stain block peak?**
- Demand is steady year-round — the busiest month runs 1.5× the quietest.
- **What does it cost to enter the stain block niche?**
- Listings span £4.40–£15.55; the average listing price is £8.83 (sweet spot $15–$100). The average incumbent carries 1,232 reviews — the moat a new listing must climb.
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