The one check that decides whether you can enter a yellow box junction, when turning right lets you wait inside it, and how examiners mark box junction mistakes.
You may enter a box junction only when your exit road or lane is clear, so you can drive through without stopping on the yellow lines. The one exception is turning right: you may enter and wait if only oncoming traffic, or other vehicles waiting to turn right, stop you. This is Highway Code rule 174.
A box junction is a junction painted with criss-cross yellow lines. You find them where a queue would otherwise block the way: at busy crossroads, across the mouth of side roads and on some roundabouts controlled by traffic lights.
The idea is simple. If drivers stop on the yellow lines, traffic from the other road cannot get through, and the whole junction locks up. Keeping the box clear keeps everyone moving.
Rule 174 uses the words MUST NOT, which in the Highway Code marks a legal requirement, not just advice.
Rule 174 says you MUST NOT enter the box until your exit road or lane is clear. Clear means there is room for your whole car beyond the yellow lines, so you can leave the box without stopping on it.
Look past the box, not at the car in front. A queue that is moving now may stop when the lights ahead change. If the space beyond the box is shorter than your car, or is filling up, wait behind the box.
Wait before the yellow lines until there is room for your car on the far side. Then drive through at a steady speed.
The same check applies to the road you are turning into. If a queue in that road reaches back to the junction, wait before the box.
This is the one exception. You may enter the box and wait when you want to turn right and the only thing stopping you is oncoming traffic, or other vehicles waiting to turn right. The road you are turning into must still have room for you. If it is blocked, do not enter.
Some roundabouts controlled by traffic lights have yellow boxes on them. Here rule 174 is stricter: you MUST NOT enter the box unless you can cross it completely without stopping.
The examiner guidance lists box junctions as a road marking under response to signs and signals, along with double white lines and lane direction arrows. The examiner wants to see you spot the marking early and react to it correctly.
DVSA's top 10 reasons for failing the test (April 2024 to March 2025) put not responding correctly to road markings at number 7. One of its examples is entering a box junction, fully or partly, when the exit is not clear. So even a car's nose on the yellow lines counts.
How it is marked depends on the risk. A driving fault is not potentially dangerous, a serious fault is, and a dangerous fault involves actual danger. Blocking traffic that is trying to cross in front of you is the kind of mistake that can be marked as serious. How driving test faults are marked explains all three types.
Box junctions can also be enforced by camera. Outside London, councils that already enforce parking can apply to the Department for Transport for powers to enforce moving traffic rules, which include yellow box junctions. Where a council has these powers, it can send a penalty charge notice based on evidence from an approved camera. Camera enforcement in London works under separate rules.
The government's statutory guidance for councils outside London says that for the first 6 months after a council starts this kind of enforcement, it should issue warning notices for first-time contraventions.
If you think a penalty charge notice is wrong, the guidance gives you 28 days from when it is served to challenge it with the council. If the council rejects your challenge, you can appeal to an independent adjudicator within 28 days. Outside London that is the Traffic Penalty Tribunal, which gives driving into a yellow box junction when the exit is not clear as an example of a moving traffic penalty.
Not every box has a camera, but the Highway Code rule applies to every box.
Box junctions sit on busy roads, so you meet them most at peak times. Ask your instructor to include some in lessons when the traffic is heavy, so you practise judging the gap with real queues.
It also helps to know where the boxes are before the day. We filmed the roads around test centres across England, including the junctions and traffic lights on them. Find your test centre and you can see the roads around it in 4K, box junctions included.
For the wider rules at junctions, read who has priority at a junction. Boxes on roundabouts with traffic lights work alongside the lane rules in roundabout lanes and signals. To check the markings and signs examiners expect you to know, try UK road signs and their meanings, and for the full plan, see how to pass your driving test.
Only when your exit road or lane is clear, so you can drive through without stopping on the yellow lines. If you are turning right, you may also enter and wait when only oncoming traffic, or other vehicles turning right, hold you up.
Yes. You may enter the box and wait to turn right if the road you are turning into is clear and the only thing stopping you is oncoming traffic or other vehicles turning right (rule 174).
At a roundabout controlled by traffic lights, you MUST NOT enter the box unless you can cross it completely without stopping. There is no waiting in the box there.
Yes, where the council has moving traffic enforcement powers and a camera covers the box. It sends a penalty charge notice, which you can challenge with the council and then appeal to an adjudicator.
Last checked: 13 October 2026.
