Never use nylon wall plugs or plasterboard anchors for safety-critical fixings. Handrails, stair rails, banisters, balustrades, gates, ladders, climbing or play equipment, overhead fixings, and anything else whose failure could cause a fall or injury need a fixing designed and rated for that purpose — typically a through-bolt, a mechanical anchor or a resin-bonded anchor with a published load rating (and, for structural use, a European Technical Assessment). If you are not certain the wall and the fixing are up to the job, get advice from a builder or structural engineer.
Wall Plug Colour Chart — UK Colour Coding Guide
There is no British Standard for wall plug colours, and colour codes differ between brands. This chart uses Rawlplug’s UNO range, which publishes its colours: yellow 5mm, red 6mm, brown 7mm, blue 8mm and grey 10mm (there is no 12mm UNO). Other brands use different colours, and fischer sells its SX, SX Plus and DuoPower plugs by size rather than by a colour code, so confirm the diameter printed on the pack.
Quick Answer
In Rawlplug’s UNO range the colours are yellow (5mm), red (6mm), brown (7mm), blue (8mm) and grey (10mm), and the drill bit is the same size as the plug. Other brands use different colours, so always check the size printed on the pack.
Complete Wall Plug Colour Chart
| Colour | Plug Diameter | Drill Bit Size | Screw | Minimum hole depth (Rawlplug UNO) |
|---|---|---|---|---|
| 🟡 Yellow | 5mm | 5mm | As on the packaging | 34mm |
| 🔴 Red | 6mm | 6mm | As on the packaging | 38mm |
| 🟤 Brown | 7mm | 7mm | As on the packaging | 40mm |
| 🔵 Blue | 8mm | 8mm | As on the packaging | 42mm |
| ⚪ Grey | 10mm | 10mm | As on the packaging | 46mm |
Recommended Wall Plugs & Fixings
As an Amazon Associate we earn from qualifying purchases. Check fitment & current price on Amazon (affiliate links).
Before you buy: check that the size, fitting/bore and maximum-rated speed marked on the accessory match what your tool’s manual specifies. We have not physically tested these products; listings are compiled from published specifications. These are affiliate links.
Hole depth: the minimums in the chart are from Rawlplug’s UNO product card; other plugs differ (fischer gives 50mm minimum for DuoPower 8×40), so use the maker’s figure for the plug you have. Load figures are not listed here because a plug’s capacity depends on the product and the wall it goes into, not on its colour. See the substrate-by-substrate load table, sourced from fischer’s published figures.
Get the free Drill Bit & Wall-Plug Size Chart (PDF)
Every drill size, wall-plug colour & tap size on one printable sheet.
The Wall Matters More Than the Colour
A plug holds far less in lightweight or aerated blocks (such as Thermalite or Celcon) or old, crumbly mortar than in solid brick or concrete. Use a fixing whose maker publishes a load for your wall type — see the substrate load table linked above.
Which Colour for Which Job?
Yellow Plugs (5mm) — Light Duty
Yellow is the 5mm UNO size, the smallest in the range. Rawlplug gives a recommended tension load of 0.43 kN per plug in solid brick. Use the screw size on the packaging and a 5mm masonry or multi-purpose drill bit.
Red Plugs (6mm) — General Purpose
Red is the 6mm UNO size. Rawlplug gives a recommended tension load of 0.71 kN per plug in solid brick. Use the screw size on the packaging and a 6mm drill bit.
Brown Plugs (7mm) — Heavy Duty
Brown is the 7mm UNO size. Rawlplug gives a recommended tension load of 0.86 kN per plug in solid brick. Use the screw size on the packaging and a 7mm drill bit. In the UNO range blue is the 8mm size, with the same 0.86 kN solid-brick figure and an 8mm drill bit.
Grey Plugs (10mm) — Largest UNO Size
Grey is the 10mm UNO size, the largest in the range. Rawlplug gives a recommended tension load of 1.00 kN per plug in solid brick. Gates, handrails, stair rails and anything else whose failure could injure someone need a fixing rated for that use, such as a frame fixing or resin anchor, chosen from the maker’s datasheet. Use the screw size on the packaging and a 10mm drill bit.
Less Common Colours
Other brands may use different colours for the same sizes, and some ranges include sizes outside the UNO range, such as fischer’s 4mm, 12mm and 14mm SX Plus plugs. Rawlplug makes no 12mm UNO plug. Go by the diameter printed on the pack.
Frequently Asked Questions
Are wall plug colours the same across all brands?
No. Colour codes are brand-specific: Rawlplug’s UNO range uses yellow 5mm, red 6mm, brown 7mm, blue 8mm and grey 10mm, while fischer sells its SX, SX Plus and DuoPower plugs by size rather than by a colour code. Always check the diameter printed on the pack.
What if my wall plug doesn’t match these colours?
Some specialist plugs (like fischer DuoPower, or frame fixings) use different colours. In these cases, ignore the colour and go by the diameter printed on the packaging. The colour chart applies to Rawlplug UNO plugs.
Can I use a wall plug that’s one size bigger than needed?
Only if you drill the hole and choose the screw to suit the bigger plug, as given on its packaging. Larger UNO sizes have higher published loads in solid brick (0.43 kN for 5mm up to 1.00 kN for 10mm, tension), but plug, hole and screw must match.
Recommended Wall Plugs
| Product | Colour/Size | Best For | Link |
|---|---|---|---|
| Fischer SX 6mm (50 Pack) | 6mm | General-purpose masonry | View on Amazon |
| Rawlplug Mixed Wall Plug Kit (272 Pieces) | Mixed | Mixed sizes | View on Amazon |
| Fischer DuoPower 6x30mm (100 Pack) | 6mm universal | Many wall types (fischer publishes a load for each) | View on Amazon |
As an Amazon Associate, we earn from qualifying purchases.
Where to Buy Wall Plugs
Colour-Coded Wall Plug Sets on Amazon
Rawlplug Assortment Boxes on Amazon
How we compile this guide
We cross-reference compatibility details against manufacturer specifications where available, official tool manuals, and the physical standards that govern fitment (bore sizes, arbor diameters, voltage platforms, connector types). We prioritise primary sources over retailer listings, flag anything we can’t confirm, and re-verify the data on a regular cycle. Where we give a buying recommendation, we tell you the reasoning — not just the link. More on our method →