Filling knife or stripping knife: flex decides the job
Updated: 21 October 2026
Filling knife or stripping knife is the choice when you already own one flat blade and today’s job is either pushing filler into a screw hole or lifting soaked wallpaper. A flexible filling knife skids on paint and paper. A stiff stripping knife drags wet filler back out of a hole and can leave a gouge. This page is only that split. Prices stay on the [filling knife comparison](/hub/painting-supplies/filling-knife). Peter F. did not run a lab test. A qualifying purchase through our links can earn us a commission at no extra cost to you.
Filling knife or stripping knife is the choice when you already own one flat blade and today’s job is either pushing filler into a screw hole or lifting soaked wallpaper.
Filling knife or stripping knife is the choice when you already own one flat blade and today’s job is either pushing filler into a screw hole or lifting soaked wallpaper. A flexible filling knife skids on paint and paper. A stiff stripping knife drags wet filler back out of a hole and can leave a gouge. This page is only that split. Prices stay on the filling knife comparison. Peter F. did not run a lab test. A qualifying purchase through our links can earn us a commission at no extra cost to you.
Our top picks
| Badge | Product | Blade flex | Stated job | Listing conflict | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Axus Decor Axus Decor Pro-Fill | Ultra-flexible, per the listing | Gaps on walls, ceilings and wood | Dimensions row is 53 cm by 7 cm | 8.0 | about £5.39 | View offer |
| Alternative |  ROLLINGDOG ROLLINGDOG set | Some reviews wanted more flex | Fill, scrape, and remove caulk | Title also says wallpaper scrapers | 6.3 | about £25.99 | View offer |
 Harris Harris Seriously Good | Flexible stainless blades | Small holes, cracks and filler | Recommended-uses line is in German | 8.5 | about £5.04 | View offer |
On this page
The bend is the specification
Toolstation lists a flexible filling knife for gaps, a rigid stripping knife for wallpaper or paint, and a putty knife with a bolstered hardwood handle. ProDec says filling knives are thinner and flex into holes, while scrapers stay thick. Thomas Graham’s test: a flexible blade flattens to spread filler, but it bows away from old coatings. A stiff blade lifts paint or paper because it does not give.
A listing photo can still look identical. Harris and ZAVIA here are continental filling shapes. Axus bullets name walls, ceilings, wood and gaps, not wallpaper stripping. ROLLINGDOG also says wallpaper scrapers while the bullets mention spreading filler. Bend the blade. Width and handle, once you want a filling knife, are on the filling knife buying guide.
What happens if you use the wrong one
Fill a hole with a stripping knife and the stiff edge tends to scrape filler out on the return stroke, especially on a shallow screw hole. The blade may chip plaster at the lip because it does not flex into the contour. Feather a wide patch with a scraper and you fight the steel.
Strip wallpaper with a filling knife and the flexible steel slides along the paper. B&Q’s wallpaper removal guide expects a stripping knife kept as flat as possible so corners do not dig into plaster, with short sharp movements, and scoring with a perforating tool rather than a random point. Putty knives sit between the two: often stiffer than a filling blade, for putty and general scraping. The press, level, wash and dry sequence is on how to use a filling knife.
A title that says both
ROLLINGDOG model 50361 is titled as filling knives and wallpaper scrapers. Bullets name scraping, cleaning, wall repairs, spreading filler, and removing caulk and joint compound. Reviews include sealant and filler, a 2 inch blade that snapped on nail holes under light pressure, and blades some users found stiffer than they wanted for filling. Marketing both jobs does not make the thin blade a chisel.
Press the tip against the bench. A filling knife should flex noticeably. A stripping knife should resist. If you need wallpaper removal, keep a stripping knife shaped for that job. Wallpaper hanging method is beyond this page. The point is which knife class belongs at the wall.
Old paint is a different rule
Stripping paint on pre-1980s UK homes can disturb lead pigment. HSE notes lead was common until the 1960s and remained in some paints into the early 1980s. PaintSafe adds that some lead may remain in paint supplied into the 1990s. Leave sound paint and overcoat it. Where paint is failing, HSE warns against blow lamps, favours wet methods, and cites trade controls such as heat below 500 °C and RPE with an assigned protection factor of 20 (FFP3 as an example). Dry scraping is the wrong reflex.
If children or pregnant occupants share that house and paint is flaking, read HSE and PaintSafe before you choose a blade. Filling a stable hairline over sound paint is a different job, on filling knife for wall cracks.
Common questions
What is the difference between a filling knife and a stripping knife?
Flex and thickness. A filling knife bends so you can press filler into a hole and feather it level. A stripping knife stays stiff so it can lift wallpaper or paint. Toolstation and ProDec use that split. Press the tip. A photo of a flat blade does not settle it.
Can you fill with a stripping knife?
Poorly. The stiff edge pulls filler back out on the return stroke, and it can chip plaster at the lip of a screw hole. Use a flexible filling blade for compound. Keep the stripping knife for paper or paint, held flat so the corners do not dig.
Can you strip wallpaper with a filling knife?
Not well. The flexible steel skids along the paper. B&Q’s wallpaper steps expect a stripping knife kept flat, with short sharp movements, after you score the paper with a perforating tool. A filling blade is the wrong shape for that lift.
Where does a putty knife fit?
Toolstation’s putty knife is the bolstered hardwood tool for window putty and general scraping. It is usually stiffer than a filling blade, so it feathers a flat wall poorly. Painters World keeps the three knives apart. The amazon.co.uk aisle often does not.
What about old paint and lead?
Sound paint can stay and be overcoated. Flaking paint in a pre-1980s UK home is a lead question. HSE notes lead into the early 1980s, and PaintSafe notes some into the 1990s. If children or pregnant occupants share the house, read those sources before you dry-scrape a flake.
Is a knife titled wallpaper scrapers a stripping knife?
Not automatically. ROLLINGDOG mixes filling knife and wallpaper scrapers on one title, and the bullets also name spreading filler. One review says a 2 inch blade snapped on nail holes under light pressure. Measure the flex before you assign that job.
Related pages
Sources
Public UK sources used for this comparison. Listing prices, stars and review counts are the amazon.co.uk figures saved for these four ASINs. The Harris price was also noted by Morris and Mica on 17 October 2026.
- Toolstation, filling and putty knives (retrieved 17 October 2026)
- ProDec Advance 2 inch filling knife (retrieved 17 October 2026)
- Harris Ultimate 2 inch filling knife (retrieved 17 October 2026)
- Polycell Multi Purpose Polyfilla ready mixed (retrieved 17 October 2026)
- Toupret, hairline cracks (retrieved 17 October 2026)
- HSE, lead in construction (retrieved 17 October 2026)
- HSE, sanding plasterboard joints (retrieved 17 October 2026)
- Consumer Rights Act 2015, section 11 (retrieved 17 October 2026)
- British Coatings Federation, PaintSafe (retrieved 17 October 2026)