stain block
Skip itPrices mostly outside the sweet spot ($4.40–$15.55) — this niche doesn't clear our bar today.
Returns
Incredible0.8%return rate — above 5% kills the launch gate
Conversion
Great11.7%search→purchase rate — share of searches ending in a sale
Quality gap
Great4.2★avg incumbent rating — lower means beatable quality
Review moat
Good1,231.92avg incumbent reviews — the moat a new listing must climb
Brand share
Okay87%top-5 brand share — brands hold most of the demand
Avg price
Okay£8.83avg listing price — sweet spot $15–$100
Competition
Bad79%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–£15.55cheapest 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
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.No pronounced peak months · busiest ÷ quietest = 1.5×
Top stain block search terms
- stain block23K/yr
- stain blocker spray16K/yr
- stain block spray4K/yr
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.
All 13 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Everbuild Stain Block Highly Pigmented Easy to Use White 400ml
Everbuild£6.514.4★4,385 rev
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£6.714.3★439 rev
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£10.124.3★3,347 rev
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£6.374.3★2,532 rev
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£8.944.2★416 rev
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£8.0379 rev
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£8.72102 rev
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£6.71439 rev
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£6.64184 rev
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£8.94416 rev
Trending
90-day click momentum
Zinsser ZINCSP400A 400 ml Cover Stain Primer/Finish Aerosol
Zinsser£10.544.6★
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£8.944.2★
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£8.724.0★
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£8.034.3★
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£10.124.3★
What buyers say about stain block
What buyers praise and complain about, mined from review topics.What buyers love
“Just what I needed”
“Excellent coverage”
“Covered the water stain completely”
“Easy to use”
“Does the job”
“Good coating really”
“Covers well”
“Good Value For Money”
“I found a soft brush made it easier”
“Its very easy to apply — quick spray, decent coverage, and no complicated prep beyond the obvious cleaning”
What buyers complain about
“Stain cover Paint”
“It smells terrible”
“One of these cans will not spray at all”
“Water leak through ceiling”
“Poor quality”
“The coverage is very poor”
“Doesn't work”
“Waste of money”
“There was a terrible water mafk which was dark yellow on my ceiling”
“Doesnt do what it says on the tin”
Top return reasons
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.