Worker Safety - Experience factor

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Experience factor

Source: WSDOT Office of Human Resources and Safety.

Note: The Washington State Department of Labor & Industries individually adjusts the base rates for premiums using an "experience factor," which L&I calculates annually for each business and government entity. This factor is a prediction of how a business's future claim costs will compare to their risk classifications. For example, if a business's claim cost costs are likely to be higher than other businesses in their risk classifications, L&I will assign an experience factor greater than 1. For more information, visit

Performance analysis


WSDOT's experience factor decreases 15.9% for 2023

In 2023, WSDOT's experience factor decreased 15.9% to 1.0590 from 1.2604 in 2022. Experience factors are based on three-years of reported data, and data for 2023 was collected between July 2018 and June 2021. As the experience factor drops, the cost of employees' workers' compensation premiums is reduced. WSDOT's goal is to be at or below 1.0000, which is the industry standard.

An experience factor is the ratio of the actual costs of workers' compensation claims at a business compared to the expected costs for businesses of similar size in the same industry. A lower experience factor translates to lower workers' compensation premiums.

The calculations include three years of claims data, excluding the most recent year. To determine comparable businesses, Labor & Industry reviews factors like the occupational classifications of employees (for example, construction, manufacturing, and managerial occupations), the number of employees, and payroll size.

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