Mandatory signs
⏱️ 4 min read
A fully blue disc with a white symbol: that is a mandatory sign. Unlike a prohibition sign, which tells you what you may not do, this one requires a specific behaviour from you: follow a direction, use a track, drive at a minimum speed. Learning to tell them apart at a glance will save you plenty of mistakes in the theory exam.
✨ Key takeaways
- Mandatory signs are blue discs with a white symbol.
- They require a specific behaviour; failing to follow them is an offence.
- Blue circle = obligation; circle with a red border = prohibition.
- Arrows (D1) impose a direction or the side on which to pass an obstacle.
- D7 obliges cyclists to use the cycle track.
- A minimum-speed sign forbids driving more slowly than the value shown.
What are mandatory signs for?
Mandatory signs require road users to behave in a specific way: take a given direction, pass an obstacle on a specific side, use a lane reserved for a category of road users or keep to a minimum speed. They do more than warn like danger signs do: they command. Failing to obey them is an offence.
How do you recognise them?
A mandatory sign is instantly recognisable by its shape and colours: a disc (solid circle) with a blue background, bearing a white symbol — most often one or more arrows, or the silhouette of a road user. It is this round + blue combination that places it in the mandatory family.
Obligation or prohibition: do not mix them up
This is the most common mix-up in the exam. Both families are round, but their colours say the opposite of each other. The prohibition sign has a white background with a red border (often a red bar across it): it forbids. The mandatory sign is entirely blue: it requires.
The main mandatory signs
- Compulsory direction (D1 series): a white arrow shows the direction to follow — straight ahead, right, left, or a combination. You are required to take the direction shown.
- Passing an obstacle: a curved arrow requires you to pass to the right (D1) or to the left of the obstacle or refuge indicated.
- Compulsory gyratory direction (D5): three arrows arranged in a circle; you must go round the central island in the direction shown. It is the typical roundabout sign.
- Compulsory cycle track (D7): a white bicycle on a blue background; cyclists (and class A moped riders) must use it, and other vehicles may not travel on it.
- Compulsory path for pedestrians, horse riders or cyclists (D9 and related): a path reserved for one or more categories of vulnerable road users, shown in white.
- Compulsory minimum speed: a white number on a blue background (e.g. 30); you may not drive below that speed, unless necessary.
- Snow chains compulsory: a tyre fitted with chains, in white; on the stretch concerned, at least two driving wheels must be fitted with them.
Where and until when do they apply?
A mandatory sign applies from the spot where it is placed. Compulsory-direction signs are generally installed on the approach to a junction or to the obstacle they concern. For a reserved path (cycle track, pedestrian path), the obligation applies along the whole length of the path; an end sign may mark its limit. An additional panel placed underneath may restrict its scope (for example to certain categories of road users or to specific hours).
What you should do
- Identify the white symbol: it tells you exactly what you must do.
- Carry out the obligation from the spot indicated (take the direction, move onto the reserved lane, etc.).
- Check for an additional panel that might limit or clarify the obligation.
- Follow the obligation until an end sign, a junction or the end of the path concerned.
| White symbol | Code | What it requires |
|---|---|---|
| Arrow(s) | D1 | Follow the direction shown / pass the obstacle on the side shown |
| Arrows in a circle | D5 | Go round the island in the gyratory direction (roundabout) |
| Bicycle | D7 | Compulsory cycle track for cyclists |
| Pedestrian (and/or horse rider, bicycle) | D9 and related | Path reserved for the category or categories shown |
| Number (e.g. 30) | Minimum speed | Drive at least at the speed shown |
| Tyre with chains | Snow chains | Fit chains to at least two driving wheels |
❓ Frequently asked questions
What shape is a mandatory sign in Belgium?
A disc (solid circle) with a blue background bearing a white symbol. This round + blue combination sets it apart from the other families of signs.
What is the difference between a mandatory sign and a prohibition sign?
Both are round. The mandatory sign is entirely blue and requires you to act in a certain way; the prohibition sign has a white background with a red border and forbids you something. In short: blue = do, red = do not.
Does the "compulsory cycle track" sign really oblige me to leave the carriageway?
Yes. On a bicycle, the D7 sign obliges you to use the cycle track; you may not ride on the carriageway alongside it. Motor vehicles, for their part, may not travel on that track.
What does a blue disc with a white number mean?
It is a compulsory minimum speed: you may not drive below that speed, unless circumstances require it. Do not confuse it with a speed limit (white disc with a red border), which sets a maximum.