Base Rates

Base rates are the benchmark premium rates for each risk classification. The same base rates are used by all Washington employers in a given classification before modification by the experience factor. There are three separate base rates for each classification:

• Accident Fund:
  Provides for wage replacement, permanent disability and death benefits, as well as certain vocational rehabilitation benefits for injured workers.
• Medical Aid Fund:
  Provides for medical care and vocational rehabilitation counselor services for injured workers.
• Supplemental Pension Fund:
  Provides for cost of living adjustments (COLA) for injured workers receiving extended wage replacement benefits.

For the accident and medical aid funds, the base rates reflect the estimated cost of providing insurance for work in that risk classification. The Supplemental Pension hourly rate is the same for all classes rated per hour worked and is not related to the risk in the class.

Learn more about the development of the classification base rates:

• Setting Accident and Medical Aid Fund Base Rates.
• Setting Supplemental Pension Fund Base Rates.

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Additional information

WAC 296-17-895 (www.leg.wa.gov)
Accident and Medical Aid Fund Base Rates for most risk classes.

WAC 296-17-920 (www.leg.wa.gov)
Supplemental Pension Fund Base Rates for hourly rated risk classes.

WAC 296-17-89502 (www.leg.wa.gov)
Accident, Medical Aid and Supplemental Pension Fund Base Rates for risk classes rated per square foot.

WAC 296-17-89504 (www.leg.wa.gov)
Accident, Medical Aid and Supplemental Pension Fund Base Rates for Horse Racing classes.

Base Rates by Risk Classification and Fund (60 KB MS Excel).