New research from The AA has revealed significant shortcomings in drivers’ understanding of stopping distances and the recommended two-second rule.

It raises fresh concerns about tailgating and road safety across the UK.

The findings come as safety professionals urge more effective driver training and public education to combat dangerous driving behaviours that contribute to crashes and near-misses every day.

Closing the gap

The AA surveyed thousands of drivers to assess their knowledge of key safety practices, including how to judge safe following distances and when to adjust for different speeds and weather conditions.

Results showed that a large proportion of motorists cannot correctly estimate stopping distances.

What’s more, unfamiliarity with the two-second rule, a basic guideline intended to ensure a safe gap between vehicles under normal driving conditions, also seems to be a common issue.

Under the two-second rule, drivers should ideally allow a two-second gap between their vehicle and the one in front, increasing this to four seconds or more in wet or poor weather.

This simple measure helps ensure there is enough time and space to react and brake safely if the vehicle ahead suddenly slows or stops.

However, the AA’s research suggests that many drivers do not consistently follow this guidance — or misjudge what constitutes a safe gap.

Too many, too close

The inquiry found that around one in three drivers underestimate stopping distances at typical motorway speeds, and a similar number cannot correctly identify the recommended separation under the two-second rule.

A significant minority even admitted to following other vehicles “closely” in heavy traffic or adverse weather, increasing the risk of rear-end collisions.

Tailgating is one of the most common causes of crashes on UK roads, particularly on busy dual carriageways and motorways.

The AA estimates that thousands of collisions each year involve tailgating or inadequate space to stop in time, with many more near-misses going unreported.

Contributors to this behaviour include frustration with traffic, overconfidence in one’s braking ability, and a lack of understanding of how speed and conditions affect stopping distance.

Worrying trends

AA President Edmund King described the findings as “deeply concerning” and called for a renewed focus on driver education.

“Stopping distances are not just abstract numbers — they represent the space and time you need to avoid a collision,” he said.

“When drivers follow too closely, they are reducing their reaction time and leaving themselves no margin for error. That’s especially dangerous in wet or icy conditions, where braking distances can more than double.”

Research by the Department for Transport (DfT) backs up these safety concerns.

Official data consistently shows that poor judgement of stopping distances is a contributory factor in many injury collisions, particularly in high-speed environments.

In wet weather, stopping distances can increase by up to four times compared with dry conditions, yet many drivers fail to adjust accordingly.

Measuring up

Road safety campaigners are calling for better training and assessment of these basic but crucial skills.

They argue that current driver education places insufficient emphasis on real-world stopping requirements and the calculation of safe following distances.

There have been suggestions that practical demonstrations, such as using simulation tools or in-car exercises, could help drivers better internalise these rules.

Tailgating also carries legal penalties. Under UK law, driving “without due care and attention” can lead to fines, points on a licence, or even disqualification in serious cases. Yet enforcement remains difficult on fast-moving, congested roads, meaning prevention through understanding and behaviour change is vital.

The AA is urging drivers to refresh their knowledge of the Highway Code and to apply the two-second rule on every journey consciously.

“It’s not enough to know the rule in theory,” King said. “You need to practise it every time you drive, and adjust the gap for weather, visibility and road conditions. That small extra space could save a life.”

Driving at safe distances remains a cornerstone of road safety, providing time and space to react, and the failure to value this skill is all too apparent in the collision data and drivers’ recorded bug bears.

The AA warns that too many motorists still do not take it seriously enough.