Salt Lake City still ranks No. 67 safest among America's 200 largest cities for car-collision frequency, falling four spots since last year.
West Valley City ranked No. 80 out of 200 this year, after being combined with Salt Lake City in last year's report. West Valley drivers average an accident every 9.4 years, or 6 percent more frequently than average.
The data is based on claims filed with Allstate.
"We don't want drivers in Salt Lake City to be discouraged by their ranking. Instead we want the report to challenge drivers in Salt Lake City to make positive changes to their driving," said Ryan Larson, an Allstate agency owner.
Fort Collins, Colo., ranks as the nation's safest driving city for the fourth time in the study's 10 years, with drivers averaging an accident once every 14.2 years.
The nation's worst drivers were in Worcester, Mass., where a typical driver has an accident once every 4.3 years. It is joined at the bottom of rankings by Boston; Washington, D.C.; and Springfield, Mass.
For the first time, the study also looked at how cities rank in crashes when factors such as bad weather, dense population or big population are considered.
For crashes during precipitation, Salt Lake City ranked No. 70 nationally and West Valley City was No. 83.
For crashes in driving conditions affected by dense population (such as more congestion), Salt Lake City ranked No. 117 and West Valley City was No. 64.
For accidents in driving conditions affected by cities with big populations (including more confusing interchanges and routes), Salt Lake City ranked No. 126 and West Valley City ranked No. 82.
Allstate said its research found that 70 percent of vehicles involved in auto claims are considered drivable, which indicates that most claims are the result of low-speed collisions under 35 miles per hour.
The company also made numerous suggestions that it says helps to reduce crashes. They include: allow plenty of time to reach your destination; get directions for where you are going; keep a safe distance; and stay alert.