Tema 15: speed in the DGT exam

The answer depends on three variables at once: road type, vehicle category and whether you tow. Memorising one number is the fastest way to fail.

Reviewed on 11 October 2026 · sources: BOE and DGT

This tema asks which limit applies depending on road type, vehicle category and whether you tow.

In a built-up area (poblado) the limit is 20, 30 or 50 km/h: 20 where carriageway (calzada) and pavement share a single surface, 30 with a single lane in each direction and 50 with two or more lanes in each direction.
On a through road in a built-up area (travesía) the limit is 50 km/h for every kind of vehicle.
A passenger car (turismo) does 120 km/h on a motorway (autopista) and dual carriageway (autovía), and 90 km/h on a conventional road.
On motorways and dual carriageways it is banned to drive under 60 km/h.
School transport and dangerous goods travel 10 km/h below their category maximum.

Watch out: a maximum-speed sign does not authorise you above the maximum for your vehicle on that road.

In DrivingLingo: see the regulatory signs, tema 31 on motorways, dual carriageways and expressways, tema 36 on rain, fog, snow and tunnels and the .

Source: RGC arts. 47, 48, 49, 50, 52.

Key rules of topic 15

20, 30 and 50 in town

In town the limit depends on how the street is built: 20, 30 or 50 km/h.

20 km/h where carriageway and pavement share a single surface.
30 km/h on streets with a single lane in each direction.
50 km/h on streets with two or more lanes in each direction.

Source: RGC art. 50.1

Through-roads and urban motorway

On a travesía the limit is 50 km/h for every kind of vehicle.

On a motorway running inside a built-up area, 80 km/h.
The town hall may lower urban limits, and exceptionally raise a single-lane street to 50.

Source: RGC art. 50.2, 50.5 y 50.6

Outside town

For a car: 120 km/h on motorways, 90 km/h on a conventional road.

Lorries, vans and a car with a trailer: 90 on motorways, 80 on conventional roads.
Buses and car-derived vehicles: 100 on motorways, 90 on conventional roads.

Source: RGC art. 48.1.a)

The minimum speed

On motorways and dual carriageways it is banned to drive under 60 km/h.

On other roads the minimum is half the generic maximum for your vehicle category.
It applies even with no other vehicle around.

Source: RGC art. 49.1; RGC art. 38.2

Moderating speed

You must be able to stop within your field of vision and before any obstacle that may appear.

You moderate especially for pedestrians, cyclists, animals, slippery surfaces, thick fog and roundabouts.
At a signed junction with almost no visibility, the maximum is 50 km/h.

Source: RGC arts. 45 y 46

Safe distance

You must leave clear space ahead that lets you stop, under hard braking, without hitting anything.

When following another vehicle without signalling an intention to overtake, vehicles with a maximum authorised mass over 3,500 kg and vehicles or combinations over 10 m in total length must leave at least 50 m so vehicles behind can overtake safely. This additional duty does not apply in built-up areas, where overtaking is prohibited, with more than one lane in the same direction, or when traffic is too congested to allow overtaking; the gap needed to avoid a collision still applies.

Source: RGC art. 54; RGC art. 95.6

Special limits

School transport and dangerous goods travel 10 km/h below their category maximum.

Cycles, mopeds and light quadricycles: 45 km/h.
Unpaved roads: 30 km/h.

Source: RGC art. 48.1.b), e) y f)

The sign beats the default

Absent a specific sign, the road's generic limit applies.

A maximum-speed sign can never authorise you above your vehicle category's generic limit.

Source: RGC art. 47; RGC art. 52

Overtaking gives no extra speed

When overtaking you may never exceed the road's speed limit: overtaking gives no extra margin.

With the generic 90 km/h limit, a car does not go above 90 while overtaking.
If a sign sets another limit, that one also applies while overtaking.

Source: RGC art. 48.1.a); RGC art. 52.1.a)

Near a school

Near a school you slow down even if you see no children, because it is a place where they are expected.

A school bus stopped at its stop is a reason to slow down even more.
In a 30 zone that limit is a maximum: you must be able to stop for a child who runs out.

Source: RGC art. 46.1.b) y e); RGC art. 45; RGC art. 50.2

Learn the rule, then practise it

Study topic 15 step by step: the rule, its citation and exam-style questions.

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