What are British Standard Colours?

Long before RAL crossed the Channel, Britain had its own colour language — and large parts of UK industry still speak it. When a refurbishment schedule calls for "Deep Brunswick green", a rail spec quotes "BS381C 114", or a local authority asks for "10-A-03", they're using the British Standard colour ranges. This guide explains the two ranges that matter, charts both in full, and covers how they sit alongside RAL — including the conversion traps.

Two living standards do the work. BS 4800 defines paint colours for building and construction; BS 381C defines colours for identification, coding and special purposes — the range with the services heritage. (You may also meet BS 5252, the 237-colour master framework BS 4800 is selected from, and the long-obsolete BS 2660, superseded by BS 4800 — convert old 2660 references rather than specifying them.)

BS 4800 — and how to read its codes

BS 4800 grew out of the 1972 schedule of paint colours for building, was last revised in 2011, and holds 122 colours including the brighter extension shades. Unlike RAL's sequential numbers, every BS 4800 reference describes the colour in three parts — take our own roadside green, 14-C-39 Holly green:

• Hue (14) — the colour family, even numbers 02 to 24 around the spectrum, with 00 for the neutral greys.
• Greyness (C) — letters A to E: A is nearly grey, E is the clearest, cleanest version of the hue.
• Weight (39) — how light or heavy the colour feels against others of the same greyness.

So a code is a recipe, not just a label: 18-E-53 reads as "blue family, clearest class, mid weight" before you ever see a sample. Many BS 4800 colours also carry trade names — sometimes several, which is exactly why the code, not the name, belongs in your specification.

The screen warning, as ever: the swatches below are honest approximations for orientation. British Standard colours are defined by physical masters, not RGB — confirm against a BS 4800 fan deck or coated sample before committing. Click or press any tile to copy its hex value.

BS 381C — the specification colours

BS 381 dates back to 1930 and works completely differently: it isn't a co-ordinated framework but a collection of 145 individual colours for specific jobs — identification, coding, camouflage and corporate liveries for government and the armed services. That heritage is written into the names: RAF blue-grey, Light admiralty grey, NATO green, Rail blue, Post Office red, International orange. The numbers group loosely by family — 100s blues through 600s greys and 700s violets — and many remain contractually required on rail, highways, defence and utilities work to this day.

BS or RAL — which should you specify?

Whichever your contract documents already use — consistently, and never "converted" silently mid-project. The ranges are separate systems with no exact equivalents: published cross-references give nearest matches only, and a near match can still read visibly different across a cabinet door. Our worked example from the RAL guide applies in both directions: BS 4800 14-C-39 Holly green sits closest to RAL 6025 Fern green — close, not identical. One trap worth naming: BS 4800 references are often written in the wild as if they were RAL codes ("RAL 14-C-39"). No such RAL colour exists — a three-part hue-greyness-weight code is always BS 4800.

For enclosures specifically, the traditional UK roadside palette is BS through and through — the greens and greys you see kerbside across the country, ours included. Our standard finishes are the classic roadside green and grey, and because the colour is pigmented through the GRP gelcoat rather than painted on, we can produce any enclosure in the range to the BS or RAL reference your scheme demands, with a little notice.

Quick answers

Is BS 4800 still current?

Yes — last revised in 2011 and still the working standard for UK building paintwork, especially in public-sector and local-authority specifications. BS 381C likewise remains current for identification and specification colours.

What's the British Standard equivalent of RAL 7035?

There isn't an exact one — that's the point. BS 4800 10-A-03 (Dawn grey) is the commonly cited nearest light grey, but treat any cross-reference as a starting shortlist and check physical samples where the match matters.

Why do some BS colours have several names?

The standards define the colour and the code; trade names grew up around them informally, and paint companies use different ones for the same reference. Specify by code and quote a name only as a courtesy.