10 Best Knot Blocking Primer for 2026
List of Top Rated Knot Blocking Primer from thousands of customer reviews & feedback.
Updated On August 2026 859 Reviews Studied By Customer Ratings
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2 
Ronseal Knot Block Wood Primer and Undercoat White 250ml
RONSEAL
- Guaranteed to completely block wood knots
- Ready to paint over in 4 hours
- Suitable for use on bare and previously painted wood
3 
Zinsser ZINBIN500 500 ml B.I.N Primer/Sealer Stain Killer Paint
Zinsser
- Exterior
- shellac-based primer
- unparalleled adhesion to glossy surfaces
4 
Zinsser ZINBIN1L 1 Litre B.I.N Primer/Sealer Stain Killer Paint
Zinsser
- Exterior
- shellac-based primer
- unparalleled adhesion to glossy surfaces
5 
Rustins RUSQDSBP1L Quick Dry Stain Block & Multi Surface Primer 1 Litr
Rustins
- Proven reliable Rustins technology
- Lightweight construction at just 1.56 Kgs
- High performace for the home or tradesman
6 
Zinsser ZINCSP1L 1 Litre Cover Stain Primer/Finish Paint
Zinsser
- Exterior
- Oil Based
- unparalleled adhesion to glossy surfaces
7 
Zinsser ZINBE123500 500 ml 123 Bulls Eye Primer/Sealer Paint
Zinsser
- Interior and exterior
- Adheres to all surfaces without sanding
- Seals stains, graffiti and tannin bleed. Dries in 30 minutes, recoatable in 1 hour
- Mould and mildew resistant film. Tintable to mid tone colours
- Rust inhibitive - great for new metal
8 
Rustins 5015332002207 Stain Block & Multi Surface Primer, White
Rustins
- A water based matt White stain blocker for interior and exterior use, with excellent adhesion to wood, plaster and previously painted surfaces.
- It will seal all stains that may bleed through and discolour paint
- When dry, it can be painted with any type of paint and undercoat
9 
Zinsser ZINCSP500 500 ml Cover Stain Primer/Finish Paint
Zinsser
- Exterior
- shellac-based primer
- unparalleled adhesion to glossy surfaces
10 
Ronseal Stain Block Aerosol White 400ml
RONSEAL
- Permanently blocks stains
- Quick drying
- Paint over in 4 hours
- Takes 2-3 coats
- Covers nicotine, ink, crayon, grease etc.
