Drivers are more likely to use their phones while speeding, a tendency that increases crash risk by combining two dangerous behaviors, according to a new study from the Insurance Institute for Highway Safety released on Apr. 28.
The study matters because it highlights how two risky actions—speeding and cellphone use—often occur together, potentially raising the likelihood of crashes. This research provides new insights into driver behavior using telematics data collected from insurance safe-driving apps.
“Until now, safety experts believed drivers used their cellphones most at slower speeds,” said IIHS President David Harkey. “But data from insurance companies’ safe-driving apps show that, in free-flowing traffic, the opposite is true.” The analysis found that on limited-access roads like freeways, phone handling increased by 12% for every 5 mph over the speed limit. On other types of roads with features such as intersections and stop signs, there was a smaller increase of 3% per every 5 mph above the limit.
“It’s alarming that the relationship between cellphone manipulation and speeding was the strongest on roads with the highest speed limits,” said Ian Reagan, IIHS senior research scientist who wrote the study. Reagan suggested possible reasons include riskier drivers being prone to both behaviors or stressful driving conditions leading to both speeding and phone use.
More nuanced information about driver behavior has become available through safe-driving apps tied to passenger-vehicle insurance policies. These apps collect large amounts of aggregated data by tracking speed, location, time of day, hard braking events and phone usage using smartphone sensors. For this study nearly 600,000 trips across most U.S. states were analyzed between July and October 2024; trips included had to last at least 18 minutes with significant highway driving time.
The Insurance Institute for Highway Safety has played a role in reducing road fatalities in the United States through advancements in vehicle safety and driver behavior research according to its official website. The organization includes facilities such as its Vehicle Research Center in Ruckersville, Virginia designed for crash tests and safety assessments as per its official website. It was created by three major insurance associations representing most of the U.S. auto insurance market according to its official website.
Efforts by IIHS have influenced state laws including primary seat belt requirements and graduated driver licensing programs according to its official website. In addition to ongoing research efforts aimed at minimizing deaths and injuries through education targeted at consumers and policymakers as per its official website, IIHS marked its fiftieth anniversary in 2009 with a crash test comparing vehicles from different eras highlighting improvements in automotive safety according to its official website.
“Speeding and distracted driving together are especially dangerous,” Harkey said. “This research shows the risk is greater than we once thought, but it also points to an opportunity to address both problems at the same time.”
