UK road signs aren't designed for personal expression. Every sign you see on a public highway has been authorised - its shape, its colour, its symbol, its size, the pole it stands on. The framework is TSRGD: the Traffic Signs Regulations and General Directions. Understanding TSRGD matters whether you're installing permanent signs, deploying temporary signs at a roadworks site, or trying to get a custom road sign authorised.
This guide walks through what TSRGD is, the three classes of road sign, the difference between permanent and temporary signs, when custom signs are permitted, and what TSRGD authorisation looks like in practice.
What TSRGD is
The full name: The Traffic Signs Regulations and General Directions 2016 (replacing the 2002 edition). TSRGD is a UK statutory instrument - secondary legislation under the Road Traffic Regulation Act 1984 - that prescribes every sign that may lawfully be placed on a public highway in England, Wales, and Scotland. It defines the shape, size, colour, and symbol of each authorised sign, the conditions for use, tolerances for placement, and authorisation routes for non-prescribed signs.
The companion document is the Traffic Signs Manual, an 8-chapter DfT publication explaining how to apply TSRGD in practice. Chapter 8 (Traffic Safety Measures and Signs for Road Works) is the most cited - see our separate Chapter 8 guide.
The three classes of road sign
1: Warning signs
What they look like: Triangular, red border, white background, black symbol. What they do: Alert drivers to a hazard ahead - bend, junction, slippery road, animals, road narrowing, school crossing. Examples: Bend ahead, slippery road, school crossing patrol.
2: Regulatory signs
What they look like: Circular. Red border + prohibited symbol = "you must not". Blue background = "you must". What they do: Tell drivers what they must or must not do - speed limits, no entry, no parking, give way, stop. Examples: Speed limit, no entry, give way, mandatory direction.
3: Informational and directional signs
What they look like: Rectangular, varying colours by road type - green for primary routes, blue for motorways, white for non-primary, brown for tourist information. What they do: Tell drivers where they're going and what services are available. Examples: Direction signs to towns, motorway exit signs, parking signs.
A fourth informal class covers temporary works signs under Chapter 8 - same shape/colour rules as permanent equivalents but with yellow backing boards to mark them as temporary.
Permanent vs temporary signs
| Aspect | Permanent | Temporary |
|---|---|---|
| Material | Aluminium / Zintec steel, retroreflective Class RA1 or RA2 sheeting | Recycled polypropylene (Q-sign), Correx, or aluminium |
| Mounting | Bolted to permanent posts in concrete | Cone-mounted or weighted base |
| Backing | White (or matching colour to sign type) | Yellow (Chapter 8 standard) |
| Compliance | BS EN 12899-1 | BS 8442 (and EN 13422 for cones) |
| Lifespan | 10-15 years | 3-8 years depending on use |
Browse SSUK permanent road signs and temporary road signs.
Custom road signs: when they're permitted
Route 1: Custom signs on private land
If the sign is on private land - a car park, school grounds, business park, industrial estate - TSRGD doesn't apply. You can specify any size, colour, message, or symbol. SSUK custom road signs covers this category: bespoke message, your specified size and shape.
Route 2: Custom signs on public roads with TSRGD-prescribed wording
TSRGD allows variations of certain prescribed signs - for example, a "No Parking" sign with your business name added is permitted as long as the sign type and core symbol comply. Local highway authorities approve these on a per-application basis.
Route 3: Special signs by Department for Transport authorisation
For genuinely novel signs not covered by TSRGD, the DfT can authorise a sign under Section 64 of the Road Traffic Regulation Act 1984. This is an 8-18 month authorisation process - not for routine site signage.
TSRGD authorisation process for permanent signs on public roads
- Identify the relevant Highway Authority. For most A and B roads: the local council. For motorways and trunk roads in England: National Highways. In London: TfL for the TLRN, the borough for borough roads.
- Submit an application specifying the proposed sign location, sign type (TSRGD reference), justification, and proposed installation date.
- Authority assessment confirming TSRGD compliance, sight-line requirements, and no conflicting sign already exists.
- Approval and works. Sign manufactured to TSRGD spec and installed by an accredited contractor.
Lead times vary - a routine permanent sign on a B-road can be approved in 4-8 weeks; a complex sign on a motorway can take 6+ months.
Common compliance failures
- Wrong sign size for the speed limit. A 600mm sign on a 50 mph road is undersized; a 1050mm or 1200mm version is required.
- Yellow backing missing on temporary signs. Temporary signs must have yellow backing to distinguish them from permanent signs.
- Chapter 8 advance warning signs deployed too close to the works. Advance warning distance scales with speed limit (45m at 30 mph, 110m at 60 mph).
- Custom sign that conflicts with TSRGD. A custom sign similar to (but not exactly) a TSRGD sign creates legal ambiguity.
- Faded or damaged retroreflective sheeting. A faded sign is non-compliant; the authority can require replacement.
Key takeaways
- TSRGD is UK law for road signs - non-compliance is a regulatory offence on public roads.
- Three sign classes: warning (triangular), regulatory (circular), informational (rectangular).
- Temporary signs use yellow backing; permanent signs use white or category-coloured backing.
- Custom signs are unrestricted on private land; on public roads they need authority approval.
- For site-specific signage on private land, you have total flexibility with no TSRGD restrictions.
FAQs
Q: Can I install a "Slow, children" sign outside my school on the public road? A: Probably not as a custom sign, but a TSRGD school crossing sign is the prescribed equivalent and the local highway authority can install one. Approach the council - school-route signs are usually a high priority.
Q: Are speed-limit signs the same in Scotland and England? A: Yes. TSRGD covers England, Wales, and Scotland. Northern Ireland's regulations are separate but largely harmonised.
Q: What happens if I install an unauthorised sign on a public road? A: The highway authority can issue a Section 132 notice requiring removal and can remove the sign and bill the installer. Persistent or dangerous unauthorised signs can be prosecuted under the Road Traffic Regulation Act.
Q: How do I know which TSRGD sign reference to use? A: TSRGD signs have a four-digit reference (e.g. "Diagram 605" for stop, "Diagram 670" for 30 mph). The Traffic Signs Manual lists every diagram, or search via the DfT's traffic signs gallery.