Nearly 4 million Americans are considered professional truck drivers, according to the American Trucking Association, which noted the industry employs around 8 million Americans and is responsible for hauling around three-quarters of all freight in the U.S. As recently reported, commercial auto rates were up 6.7% during 2021's fourth quarter, according to MarketScout. Insurance rates for the transportation sector were up 10.3% during the period. During 2020, the sector's combined ratio improved year on year, moving from 109.3 in 2019 to 101.8, according to AM Best. The market's combined ratio has not been below 100 since 2010. The rating agency has a negative segment outlook for commercial auto because of a decade of unprofitable underwriting results, the effect of social inflation on claims costs and challenges around prior accident-year loss reserves. The U.S. national averages for commercial truck insurance range from $640/month for specialty truckers to $982/month for transport truckers, according to Progressive Commercial. Progressive also reported the following seven factors weigh heavily when determining rates: |

• USDOT authority
• Contractual requirements
• Cargo type
• Operating radius
• Vehicle type
• Driving history
• Home state of the operation

The above slideshow highlights the leading semi-truck insurance companies, according to a review by Fitsmallbusiness.com and Investopedia.com. Related: |

• How telematics is helping commercial auto insurers through a challenging market
• Top small commercial insurers for customer satisfaction
• What's propelling commercial property rates?