How to draw an accident diagram correctly

The sketch in box 13 of the accident statement often decides who is at fault. You don't need to draw well, you need to draw clearly. Here is how, with the mistakes to avoid.

Updated November 8, 2026 · 4 min read

Box 13 of the European accident statement, the sketch, scares a lot of drivers. It shouldn't: nobody is judging your drawing. What the insurer needs is to understand, in a few seconds, where each vehicle was, where it was going, and where they touched. A clear diagram made of rectangles and arrows does that better than a careful drawing.

What the sketch must show

At the moment of impact, the sketch should show:

the road layout: the lanes, the junction or the roundabout, the parking spaces;
the position of vehicles A and B, labelled with their letters;
their direction of travel, with arrows;
the point of impact;
the road signs and markings that matter: stop or give-way signs, traffic lights, solid or broken lines, one-way streets, pedestrian crossings;
the names of the streets, if you know them.

Step by step

1. Draw the road first

Two parallel lines for a road, a cross for a junction, a circle for a roundabout. Draw the lanes with a dashed line between them, and solid lines where they are solid on the road. Keep it big: use the whole box.

2. Place the vehicles at the moment of impact

A rectangle for each vehicle, with the front marked (a small triangle or a line at the front). Write A in one and B in the other, the same letters as on the form: A is the vehicle in the left column, B the one in the right column. Swapping them is one of the most common, and most costly, mistakes.

3. Show where they were going

An arrow behind each vehicle for its path, and an arrow for where it was heading: straight on, turning, changing lane. If a vehicle was stopped or parked, say so in the sketch.

4. Mark the impact

A cross or a small star where the vehicles touched. It must match box 10 (point of initial impact) on each driver's column.

5. Add the signs, lights and markings

A stop sign, a give-way triangle, a traffic light and its colour if you agree on it, the direction of a one-way street. These details often decide who had priority.

6. Name the streets and orient the drawing

Write the street names along the roads, and if useful, add where north is or a landmark ("towards the town centre").

The golden rule: the sketch must match the boxes

Insurers read the sketch together with the circumstances ticked in box 12. If you ticked "changing lanes" but your drawing shows your car going straight in its lane, the form contradicts itself, and in a contradiction, insurers generally go by the ticked boxes. Before you sign, check both drivers' boxes against the drawing, one by one.

Common situations

Rear-end collision: one lane, B behind A, both arrows in the same direction, impact at A's rear and B's front. Box 8 for B.
Junction: a cross, the two vehicles on different roads, their arrows, and the sign or light that applies to each one. If one came from the right where priority to the right applies, say so (box 16).
Roundabout: a circle with its entries, one vehicle already on the roundabout (box 7), the other entering (box 6), each with its arrow.
Parking: the row of parking spaces, the parked vehicle (box 1) or the one pulling out (box 2), and the moving one.
Changing lanes: two lanes with a dashed line, the arrow of the vehicle crossing the line (box 10).

Mistakes to avoid

Drawing too small or too crowded. Leave out what doesn't help understand the crash.
Swapping A and B.
Forgetting the arrows, which leaves the reader guessing the direction.
A drawing that contradicts the boxes.
Drawing on the spot without thinking. If you can, do a quick draft on another sheet, or on your phone, first.
Altering the sketch after signing. Like the rest of the form, it can't be changed by one driver alone.

Drawing it on a phone

A sketch on a phone screen is easier to get right, because you can move things until they're in the right place. ZenConstat has a sketch tool with ready-made lanes, junctions, roundabouts, vehicles and road signs that you place and turn with your fingers, or you can draw freehand. The vehicles come already labelled A and B, and the result goes straight into box 13 of the PDF.

For the rest of the form, see how to fill out a European accident report.

Sources

This guide gives general information, not legal advice. Rules and deadlines vary by country and by insurance contract: when in doubt, ask your insurer.