Road and traffic signs is one of the biggest theory test topics, and one of the easiest to score well on once you understand the system behind the signs. This page explains how signs, road markings and light signals are tested, and teaches you the shape and colour rules that let you work out the meaning of a sign you have never seen. For the sign-by-sign library with every category, use our road signs hub.
Last reviewed: September 2026. Checked against the Highway Code and GOV.UK.
What this topic covers in the theory test
The theory test’s multiple-choice section has 50 questions to answer in 57 minutes (GOV.UK). Sign questions usually show you a sign, marking or signal and ask what it means, or describe a situation and ask which sign you would expect to see. You will come across:
- signs giving orders (red and blue circles, plus the STOP and give way exceptions)
- warning signs (mostly red triangles)
- direction and information signs (rectangles, colour-coded by road type)
- road markings, from give way lines to box junctions and yellow lines
- traffic lights and flashing signals, including level crossings
- motorway signals, such as the red X over a closed lane
- signals given by police officers and other authorised people
Signs also turn up outside this topic. Questions on motorway rules, rules of the road and vulnerable road users often hinge on a sign, and the hazard perception clips are full of warning signs that tell you a hazard is coming. Learning the system pays off across the whole test.
The official reference is the Highway Code’s traffic signs, road markings and light signals pages. The Highway Code points to the Department for Transport booklet Know Your Traffic Signs, which illustrates and explains the vast majority of signs you are likely to meet, and GOV.UK lists it as a revision resource for the theory test.
The shape and colour system
UK signs follow a simple code. Learn this first and a large share of sign questions become logic rather than memory.
Circles give orders
According to the Highway Code’s traffic signs page, signs giving orders are mostly circular:
- Red circles are prohibitive. They tell you what you must not do, for example a maximum speed, no entry for a type of vehicle, or no U-turns.
- Blue circles give mandatory instructions. They tell you what you must do, such as turn left ahead, keep left, or a route only for certain users.
A useful way to remember it: red circles say “don’t”, blue circles say “do”.
The two important exceptions
Two order signs break the circle rule so they can be recognised even when covered in snow or seen from behind:
- STOP is an octagon. At a junction with a STOP sign and a solid white line, you MUST stop behind the line (rule 171).
- Give way is an inverted (upside-down) triangle. At a junction with broken white lines across the road, you MUST give way to traffic on the main road (rule 172).
Triangles warn
Warning signs are mostly triangular, pointing upward, with a red border. They tell you about a hazard ahead: a bend, a junction, a school, a level crossing, slippery road, or animals. They do not order you to do anything, but they are telling you to slow down and look. See our warning signs guide for the full set.
Rectangles inform
Direction signs are mostly rectangular, and the background colour tells you the type of road:
| Background | Meaning |
|---|---|
| Blue | Motorways |
| Green | Primary routes |
| White with a black border | Non-primary and local routes |
| Brown | Tourist attractions |
Information signs are all rectangular. The direction and information signs page has examples.
Road markings
Markings on the road are as much a part of the sign system as upright signs, and many carry a legal MUST in the Highway Code. The test uses them often.
Lines along the road
- Hazard warning lines. A broken white line marks the centre of the road. When the line lengthens and the gaps shorten, there is a hazard ahead. Do not cross it unless you can see the road is clear and you wish to overtake or turn off (rule 127).
- Double white lines, broken line nearest you: you may cross to overtake if it is safe and you can complete the manoeuvre before reaching a solid line on your side (rule 128).
- Double white lines, solid line nearest you: you MUST NOT cross or straddle it unless it is safe and you need to enter adjoining premises or a side road. You may cross, if the road is clear, to pass a stationary vehicle or to overtake a pedal cycle, horse or road maintenance vehicle travelling at 10 mph or less (rule 129).
Lines across the road and in boxes
- A solid white stop line goes with a STOP sign or traffic signals. Broken give way lines go with give way signs and at roundabouts.
- Box junctions (yellow criss-cross lines): you MUST NOT enter the box until your exit road or lane is clear, but you may enter and wait when you want to turn right and are only stopped by oncoming traffic or other vehicles waiting to turn right (rule 174).
Kerbside markings
- Double yellow lines mean no waiting at any time, unless signs show seasonal restrictions.
- Single yellow lines mean no waiting during the times shown on nearby plates.
- Red routes (double and single red lines) prohibit stopping to park, load or unload, or pick up and set down passengers, during the times shown.
- Yellow “school keep clear” zigzags mean the entrance must be kept clear of stationary vehicles, even when picking up or setting down children.
The road markings guide shows each one.
Traffic lights and flashing signals
The Highway Code’s light signals section sets out the sequence. The test likes to ask about amber and about red and amber together.
| Light | What it means |
|---|---|
| Red | Stop. Wait behind the stop line on the carriageway |
| Red and amber | Stop. Do not pass through or start until green shows |
| Green | You may go on if the way is clear. Take special care if turning, and give way to pedestrians who are crossing |
| Amber | Stop at the stop line. You may go on only if the amber appears after you have crossed the stop line, or you are so close to it that pulling up might cause an accident |
Rule 176 adds that you MUST NOT move forward over the white line when the red light is showing.
Alternately flashing red lights mean you MUST stop. You will find them at level crossings, lifting bridges, airfields and fire stations. On motorways, a red X above your lane means you MUST NOT go any further in that lane. See traffic lights and signals and motorway signs for the full picture.
How to revise signs efficiently
- Learn the system before the signs. Shape and colour first, then work through each category. You will be able to reason out many unfamiliar signs.
- Use the official booklet. Know Your Traffic Signs is free on GOV.UK and is the most complete source.
- Group similar signs. Signs that look alike are where marks are lost: a red circle speed limit against a blue circle minimum speed, or a warning triangle against a give way triangle.
- Name signs out loud on real journeys. Passengers can revise too. Saying what each sign means, and what you would do, links the theory to the road.
- Test yourself on markings. Learners tend to spend all their time on upright signs and lose marks on lines.
Common mistakes learners make
- Mixing up red and blue circles. Red prohibits, blue instructs.
- Confusing the give way sign (inverted triangle) with a warning triangle (point upwards).
- Thinking green-backed direction signs are for motorways. Motorways are blue; green is for primary routes.
- Crossing a solid white line to overtake a car doing 25 mph. The exception is only for pedal cycles, horses and road maintenance vehicles at 10 mph or less, or to pass a stationary vehicle.
- Entering a box junction to go straight on when the exit is not clear.
- Treating amber as “speed up”. The rule is to stop unless you have crossed the line or cannot stop safely.
- Forgetting that a red X on a motorway gantry is a legal instruction, not advice.
Practice questions
These practice questions are written by Get Driving Test Ready to help you revise. They are not official DVSA questions.
Q1. A circular sign has a red border. What type of instruction does it usually give?
A) Directions to a tourist attraction.
B) Something you must not do.
C) Something you must do.
D) A warning of a hazard ahead.
Answer: B. Red circles are prohibitive: they tell you what you must not do. Blue circles give mandatory instructions. (Highway Code: traffic signs)
Practise this on the road: On your next drive, name each red-circle sign you pass and say what it stops you doing.
Q2. Which shape is used for the STOP sign?
A) Circle.
B) Triangle.
C) Rectangle.
D) Octagon.
Answer: D. STOP is an octagon, one of the exceptions to the rule that order signs are circular. (Highway Code rule 171; Highway Code: traffic signs)
Practise this on the road: Practise approaching a STOP junction, stopping fully at the line and looking properly before moving off.
Q3. You see a direction sign with a green background. What type of road does it refer to?
A) A motorway.
B) A primary route.
C) A local route.
D) A route for tourists only.
Answer: B. Green backgrounds are for primary routes. Motorways use blue, local routes use white with a black border and tourist signs use brown. (Highway Code: traffic signs)
Practise this on the road: Call out the colour of each direction sign you see and say what type of road it points to.
Q4. You are approaching a junction with broken white lines across your side of the road. What must you do?
A) Sound your horn before emerging.
B) Continue, as you have priority.
C) Give way to traffic on the main road.
D) Stop at the line in all cases.
Answer: C. Broken white lines across the road mean you must give way to traffic on the main road. You only have to stop if the way is not clear. (Highway Code rule 172)
Practise this on the road: Practise approaching give way junctions, slowing early and only stopping if the main road is not clear.
Q5. There are double white lines in the centre of the road and the line nearest to you is solid. A cyclist ahead is travelling at 8 mph and the road is clear. May you cross the line to overtake?
A) No, never.
B) Only if you sound your horn first.
C) Yes, but only in daylight.
D) Yes, if it is safe, because the cyclist is travelling at 10 mph or less.
Answer: D. Rule 129 lets you cross, if the road is clear, to overtake a pedal cycle, horse or road maintenance vehicle travelling at 10 mph or less. Remember to give them plenty of room. (Highway Code rule 129)
Practise this on the road: On country roads, practise spotting double white lines early and deciding whether it is safe and legal to pass a cyclist.
Q6. You want to go straight ahead at a box junction but your exit road is blocked by queuing traffic. What should you do?
A) Sound your horn to clear the traffic.
B) Wait before the box until your exit is clear.
C) Enter the box and wait.
D) Enter the box as long as the lights are green.
Answer: B. You must not enter the box until your exit road or lane is clear. The only exception is when turning right. (Highway Code rule 174)
Practise this on the road: At box junctions, practise checking your exit is clear before you move onto the yellow criss-cross lines.
Q7. The traffic lights change from green to amber as you approach. You are well back from the stop line and can stop safely. What should you do?
A) Speed up to get through.
B) Stop at the stop line.
C) Continue, as amber means proceed with caution.
D) Flash your headlights and continue.
Answer: B. Amber means stop at the stop line, unless you have already crossed it or are so close that pulling up might cause a collision. (Highway Code: light signals controlling traffic)
Practise this on the road: Practise judging when to stop as traffic lights change, keeping your speed down on the approach.
Q8. What do alternately flashing red lights at a level crossing mean?
A) You must stop.
B) The crossing is out of order.
C) Slow down and look both ways.
D) A train has just passed.
Answer: A. Alternately flashing red lights mean you must stop. They are used at level crossings, lifting bridges, airfields and fire stations. (Highway Code: light signals controlling traffic)
Practise this on the road: Ask your instructor to include a level crossing on a lesson and talk through the light sequence as you approach.
Q9. You are on a motorway and a red X appears on the signal above your lane. What must you do?
A) Slow to 40 mph and continue.
B) Move out of that lane, as you must not go further in it.
C) Stop on the hard shoulder.
D) Switch on your hazard lights and continue.
Answer: B. A red X means you must not proceed any further in that lane. Move into an open lane safely. (Highway Code: light signals controlling traffic)
Practise this on the road: On a motorway lesson, practise reading lane signals early and changing lanes smoothly when a lane closes.
Q10. What do double yellow lines along the edge of the road mean?
A) Parking for permit holders.
B) No waiting during peak hours only.
C) No waiting at any time, unless signs show seasonal restrictions.
D) Parking is allowed after 6 pm.
Answer: C. Double yellow lines mean no waiting at any time, unless there are signs that specifically show seasonal restrictions. You may still stop briefly to load or unload, or to let passengers get in or out, unless there are also loading restrictions. (Highway Code: road markings)
Practise this on the road: When looking for somewhere to park, practise checking the lines and nearby plates before you stop.
Next steps
Browse the full road signs library, starting with regulatory signs and warning signs. Then go back to the theory test hub, or read the related topics rules of the road and motorway rules. Warning signs are also your early clues in the hazard perception test.