According to recently released data from the National Association of Insurance Commissioners (NAIC, the top 25 insurance carriers writing commercial auto coverage grossed more than $45.78 billion in direct premiums written for the sector in 2020. That is slightly more than the $45.1 billion generated in 2019 and significantly more than the $42.9 billion written for commercial auto in 2018. The NAIC's 2020 Property/Casualty Market Share report offers cumulative market data reported on insurers' annual financial statements to the association as of March 29, 2021, for business conducted in the U.S. states and territories and Canada. The commercial auto sector has dealt with many challenges within the past few years, including an aging workforce, driver shortage, distracted driving, fleet maintenance and social inflation. On the insurance side, commercial auto providers have seen losses stack up year after year, resulting in premium rates increases of 10-15% annually since 2010, according to a 2020 report from Risk Placement Services (RPS). But through these challenges, the top commercial auto insurers have mostly managed to maintain their standings in NAIC's annual fillings for 2020 over the year prior. Just one new insurer — W.R. Berkley — cracked the top 15 in the category this year. Find out the top 15 commercial auto insurance carriers in 2020, according to NAIC filings, by clicking the slideshow above.  Related: 

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