Yellow box: your exit was clear when you entered
The rule is in the Traffic Signs Regulations and General Directions 2016, Schedule 9, Part 7, paragraph 11(1): a person must not cause a vehicle to enter the box junction so that the vehicle has to stop within the box junction due to the presence of stationary vehicles. That rule is subject to sub-paragraphs (2), (3) and (4) of the same paragraph. A vehicle that is stationary with only part of it inside the box still counts as stopped within the box (paragraph 11(7)). For England outside London, the Department for Transport's statutory guidance to councils says the contravention "can only occur due to circumstances present when a vehicle enters the box, and not as the result of anything unexpected occurring subsequently". That your exit was clear when you drove in is your account, for the council to check against its own footage, so this is not a guaranteed win.
Legal basis
TSRGD 2016 Schedule 9 Part 7 para 11 (the prohibition conveyed by the item 25 box junction marking); Highway Code Rule 174 (guidance); Traffic Management Act 2004 Part 6
How to identify this in your case
Watch the council's CCTV footage from the moment your car crosses the line into the yellow box. If the road ahead of you was clear at that exact moment — even if you then stopped inside the box — this ground may apply to you.
Sample appeal wording
Sample wording to adapt and send yourself — it may not fit your notice or the stage you are at.
When I entered the box junction my exit was clear. I only had to stop because of something unexpected that happened after I had entered.
Beat It writes this argument automatically
Scan your PCN — our AI checks if this ground applies to your specific ticket and drafts an appeal letter. You check it and tap send: we send it in your name where the council takes email, or through the council’s own website where we can; otherwise we guide you through their own online form so you press submit, or give you a letter to post. The win fee is only charged if you win.
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