---
title: "Filling Knife — £199K/yr Amazon UK Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/uk/diy-tools/filling-knife"
last_updated: "2026-07-31T12:34:05.663Z"
locale: en
meta:
description: "Niche score 48/100 · £199K/yr market · 229K searches/yr · £6.14 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 48/100 · £199K/yr market · 229K searches/yr · £6.14 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "Filling Knife — £199K/yr Amazon UK Niche (2026) - Flapen"
---
# **filling knife**
**Skip it**
Pricing outside the sweet spot ($6.14 avg) — this niche doesn't clear our bar today.
Market size 39Growth 19Conversion 96Competition 33Returns 99Price range 32Avg price 17Brand share 52Review moat 49Quality gap 45
**Returns**
**Incredible****0.3%**
return rate — above 5% kills the launch gate
**Conversion**
**Incredible****14.2%**
search→purchase rate — share of searches ending in a sale
**Brand share**
**Good****74%**
top-5 brand share — brands hold most of the demand
**Review moat**
**Okay****1,634.78**
avg incumbent reviews — the moat a new listing must climb
**Quality gap**
**Okay****4.5★**
avg incumbent rating — lower means beatable quality
**Market size**
**Okay****£199K**
£199K/yr · 229K searches
**Competition**
**Okay****65%**
top-5 click share — leaders hold, buyers still browse
**Price range**
**Okay****£2.07–£21.16**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Growth**
**Bad****-12.5%**
90-day search growth — must beat 0% to launch
**Avg price**
**Bad****£6.14**
avg listing price — sweet spot $15–$100
According to Flapen's Amazon United Kingdom niche tracking, filling knife is a £199K/yr Amazon United Kingdom market (229K searches/yr). The top 5 brands hold 74% of demand. Verdict: Skip it — 48/100.
Data updated Jul 22, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **filling knife market data**
- **Units sold / yr**
- **30K–40K**
- avg 2,000–2,500/product
- **Revenue / yr**
- **£184K–£246K**
- units × avg price
- **Conversion rate**
- **14.2%**
- **Avg BSR**
- **#15**
- **Page quality**
- **0%**
- **Prime**
- **100%**
- **Sponsored**
- **33%**
- **Out of stock**
- **5.0%**
- **Avg brand age**
- **42 months**
- **Avg seller age**
- **169 days**
## **Competition & brand share**
The top 5 products take 65% of clicks — established leaders, but buyers still shop beyond them.
**Brands**
**14 **▼falling
**Sellers**
**75**
**Top-5 brand share**
**74%**
Top 20: 100%
**Top-5 click share**
**65%**
Top 20: 100%
**Open market**
**22%**
- Harris41% - KZXXZH14% - Axus Decor8% - YWYHHM6% - Sukudon5% - G4GADGET4%
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — -12.5% search growth over the last 90 days.
5K3KSpike '25 seasonSepDecMarJunAugNovMarMay
No pronounced peak months · busiest ÷ quietest = 1.6×
[**Open Trend **](https://flapen.com/research/uk/diy-tools/filling-knife/trend)
## **Top filling knife search terms**
- **filling knife**78K/yr-7.8%8.3% conv. - **filler knife**43K/yr-13.8%10.6% conv. - **filler tool**27K/yr-12.9%11.1% conv. - **filling knife set**21K/yr-11.4%6.7% conv. - **wall filler tool**9K/yr-10.4%11.3% conv. - **filling knives**10K/yr-25.5%7.0% conv. - **flexible filling knife**6K/yr-21.6%7.3% conv. - **filler scraper**5K/yr-16.1%12.7% conv. - **filler knife for walls**5K/yr-25.3%12.0% conv. - **filling blades**5K/yr-3.1%6.6% conv. [**All search terms **](https://flapen.com/research/uk/diy-tools/filling-knife/search-terms)
## **Top filling knife 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%£20K20%£40K30%£60K40%£80K1101001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 18 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**Harris Seriously Good Continental Filling Knives 4 Pack 102064328**Harris**£2.31**4.6★3,920 rev](https://www.amazon.co.uk/dp/B0866PJXCX) [2**KZXXZH Wallpaper Scrapers 1.5 3 4 5 Wide Putty Knife Set Metal Spackle Knives Paint Tools for Wallpaper/Decals/Drywall Finishing/Plaster Scraping (4 Pack)**KZXXZH**£5.38**4.5★2,887 rev](https://www.amazon.co.uk/dp/B094H9373N) [3**Harris Trade Filling Knife 2**Harris**£4.01**4.6★106 rev](https://www.amazon.co.uk/dp/B0CYHBRCZ4) [4**7 Piece Stainless Steel Wallpaper Scraper and Paint Tool Set With Filling Knives Spackle Drywall Joint Filler Putty Knife for Plastering Walls - Includes Tool Bag Hand Tools Gifts for Men**YWYHHM**£12.45**4.3★139 rev](https://www.amazon.co.uk/dp/B0C2DDRPG7) [5**Sukudon 4 Pieces shankless Blade Painting Tools Seriously Good Continental Filling Knives (45MM+65MM+85MM+105MM)**Sukudon**£4.93**4.4★262 rev](https://www.amazon.co.uk/dp/B096TPYWRV)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**G4GADGET Wallpaper Scraper 3 Inch Stainless Steel Paint & Putty Scraper with Soft Grip Handle Heavy Duty DIY Scraper Tool for Wallpaper Steamer Removal Drywall Filler Glass/Window & Hob Cleaning**G4GADGET**£3.33**8 rev8mo ago](https://www.amazon.co.uk/dp/B0G3QNQD6R) [**ZAVIA Continental Filling Knives Pack of 4 | Flexible Filling Knife | Stainless Steel Filler Spreader | Filling Knife Set for Holes Cracks & Walls | Filler Knife with Plastic Grip (Standard)**ZAVIA**£3.40**29 rev10mo ago](https://www.amazon.co.uk/dp/B0FPG2B47B) [**WINICE Paint Scraper Set 4 Pack Stainless Steel Putty Knives (2 4 6 8) with Soft Grip Handle Wallpaper Remover & Plastering Tools for Drywall Paint and Wall Repair**WINICE**£8.96**82 rev1y ago](https://www.amazon.co.uk/dp/B0FH5K4DM6) [**DEKEones 5 PCS Wallpaper Scrapers Set Stainless Steel Wall Filler Scrapers Strippers Remover 4 Paint Scrapers and 1 Multi Scraper Tool Filling Paint Stripper for Drywall Decals (1 3 4 6 10)**DEKEones**£11.76**3,406 rev1y ago](https://www.amazon.co.uk/dp/B0F5M38J4D) [**Harris Trade Filling Knife 2**Harris**£4.01**106 rev2y ago](https://www.amazon.co.uk/dp/B0CYHBRCZ4)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**G4GADGET Wallpaper Scraper 3 Inch Stainless Steel Paint & Putty Scraper with Soft Grip Handle Heavy Duty DIY Scraper Tool for Wallpaper Steamer Removal Drywall Filler Glass/Window & Hob Cleaning**G4GADGET**£3.33**4.4★**▲ 308%**](https://www.amazon.co.uk/dp/B0G3QNQD6R) [**WINICE Paint Scraper Set 4 Pack Stainless Steel Putty Knives (2 4 6 8) with Soft Grip Handle Wallpaper Remover & Plastering Tools for Drywall Paint and Wall Repair**WINICE**£8.96**4.4★**▲ 143%**](https://www.amazon.co.uk/dp/B0FH5K4DM6) [**Axus Decor Pro-Fill (Blue Series) Stainless Steel Flexible Filling Knife Filler Knife - Putty Knife for Professional & DIY Projects - Anti Rust Blade and Rubberized Handle - 2 Inch/ 50mm**Axus Decor**£4.96**4.7★**▲ 88%**](https://www.amazon.co.uk/dp/B00NY2DSR8) [**ZAVIA Continental Filling Knives Pack of 4 | Flexible Filling Knife | Stainless Steel Filler Spreader | Filling Knife Set for Holes Cracks & Walls | Filler Knife with Plastic Grip (Standard)**ZAVIA**£3.40**4.2★**▲ 65%**](https://www.amazon.co.uk/dp/B0FPG2B47B) [**Sukudon 4 Pieces shankless Blade Painting Tools Seriously Good Continental Filling Knives (45MM+65MM+85MM+105MM)**Sukudon**£4.93**4.4★**▲ 31%**](https://www.amazon.co.uk/dp/B096TPYWRV)
**~~View all trending →~~**
## **What buyers say about filling knife**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Quality-Overall**31%
*“Excellent product”*
**Value For Money**15%
*“Good price”*
**Advertised Vs Actual Product**9%
*“works as it should”*
**Ease Of Use**9%
*“Comes in handy”*
**Size-Overall**5%
*“Great variety of sizes”*
**Ease Of Cleaning**5%
*“clean up well after use”*
**Durability**3%
*“durability is very good”*
**Grip**3%
*“Comfortable grip handel”*
**Strength**3%
*“not flimsy”*
**Flexibility**2%
*“get the job done without bending”*
### **What buyers complain about **
**Quality-Overall**22%
*“I know theyre cheap”*
**Strength**20%
*“not as robust as they look”*
**Value For Money**9%
*“expensive for just a small bit of plastic”*
**Size-Overall**5%
*“leaves to bigger bead”*
**Product Condition**4%
*“Unfortunately this item came filthy as if it was already used”*
**Thickness**4%
*“Very thin and cheaply made”*
**Defective Material/Parts**4%
*“One of the handles was faulty”*
**Rusts/Corrodes**4%
*“However, they begin to rust as soon as they come into contact with water”*
**Ease Of Use**4%
*“Couldn't use it”*
**Advertised Vs Actual Product**4%
*“didn't do as advertised”*
### **Top return reasons **
**Quality-Overall**29%
**Size-Overall**11%
**Functionality-Overall**11%
**Material Quality**8%
**Product Condition**7%
**Sharpness**6%
**Strength**6%
**Compatibility-Overall**5%
**Defective Material/Parts**4%
**Thin**3%
## **Common questions**
- **Is filling knife profitable to sell on Amazon United Kingdom?**
- The niche generates £199K/yr across 18 tracked products. 1 of 2 products launched in the last 360 days are still selling. 90-day search growth is -12.5%. Flapen's verdict: Skip it (48/100).
- **How competitive is the filling knife niche?**
- 14 brands and 75 sellers compete. The top 5 products take 65% of clicks and top 5 brands hold 74% of demand.
- **What do buyers complain about in filling knife?**
- Top complaints mined from reviews: Quality-Overall, Strength, Value For Money. The return rate is 0.3%.
- **When does demand for filling knife peak?**
- Demand is steady year-round — the busiest month runs 1.6× the quietest.
- **What does it cost to enter the filling knife niche?**
- Listings span £2.07–£21.16; the average listing price is £6.14 (sweet spot $15–$100). The average incumbent carries 1,635 reviews — the moat a new listing must climb.
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