A new report from the AA has revealed that motorists driving well below the speed limit can be just as dangerous as those breaking it.

It is prompting calls for road safety campaigns and driver training to recognise the risks posed by excessively slow drivers.

Two-way speed

The AA analysed government collision data over the past decade and found that 19 people have been killed and more than 1,500 injured in crashes where “driving too slowly” was listed as a contributing factor.

In total, there were 1,090 collisions in which police officers recorded slow driving as a cause, and experts say that figure could be far higher due to underreporting.

Slow drivers often cause following drivers to take rash, unnecessary and potentially dangerous actions.

Still, when it comes to crash reports, this potentially initial ingredient in the mix is not recorded, and therefore it is not justly recognised in dangerous driving reports and campaigns.

While speeding remains one of the leading causes of road deaths, the AA’s new findings highlight the opposite end of the problem – drivers travelling too slowly for the conditions, often well below the flow of surrounding traffic.

AA President Edmund King said:

“We all know that excessive speed kills, but inconsiderate driving that’s too slow for the conditions can also create serious risks. It causes frustration, encourages risky overtaking and can lead to tailgating or sudden braking. This report shows we need to take the issue far more seriously.”

Disruption and danger

According to the AA, slow drivers often create “rolling roadblocks” that can lead to aggressive overtaking or collisions when other motorists attempt to pass.

On fast-moving roads, such as motorways or dual carriageways, vehicles driving far below the average speed can disrupt traffic flow and force other drivers to make sudden adjustments.

Road safety experts say this can be particularly hazardous for heavy goods vehicles and for drivers joining or leaving high-speed roads.

The Department for Transport notes that driver error and “injudicious action” remain major causes of road crashes, and that inappropriate speed, whether too fast or too slow, is a significant factor.

Research from the Transport Research Laboratory supports this, showing that vehicles travelling much slower or faster than the average flow have a higher crash risk, a phenomenon known as the Solomon Curve.

Rethinking education

The AA’s report calls for greater awareness of the dangers of slow driving to be included in driver education and advanced training.

Current driver training and testing focus heavily on the risks of speeding, but rarely mention the potential consequences of under-speeding or obstructive behaviour.

King added: “We’re not talking about people driving carefully or adjusting to weather conditions – that’s good driving. But sitting at 35mph on a clear 60mph road or 40mph on a motorway slip road can be dangerous. Instructors and examiners should discuss these risks with learners, just as they do with speeding.”

Minimum speed

The AA has stopped short of calling for new laws or the introduction of widespread minimum speed limits, but says the issue needs to be discussed more openly in the context of modern traffic conditions.

Some stretches of motorway already have minimum speed signs, yet they are rarely enforced.

Safety group RoadsafetyGB echoed the AA’s concerns, noting that slow driving often goes unnoticed until it causes an incident.

“It’s a misconception that only fast drivers are dangerous,” a spokesperson said. “Slow driving can cause frustration, risky overtakes and unpredictable traffic patterns – all of which increase the chances of a crash.”

A balanced approach

The AA’s message is simple: responsible driving means matching your speed to the road, the weather, and the surrounding traffic – not just staying below the limit.

As the UK continues to promote Vision Zero, a government strategy aimed at eliminating all road deaths and serious injuries, the AA says it’s time to address the full spectrum of risky behaviour on the roads.

“Speeding remains a huge problem,” King concluded, “but this report shows that driving too slowly for the conditions can also destroy lives. Safe driving is about balance, awareness and confidence – and we need our training, enforcement and campaigns to reflect that.”