OLYMPIA, WA – Washington State officials have released an evaluation of the state’s single-use plastic bag ban.

The law, enacted in 2021, prohibits single-use plastic carryout bags, requires thicker plastic bags, and imposes a pass-through charge for customers. The Department of Commerce and Department of Ecology contracted Washington State University to study the law’s effects.

The WSU study found that while the number of plastic bags distributed dropped by 50% from 2021 to 2022, total plastic use by weight increased 17% due to the heavier reusable 2.25 mil bags. Paper bag use decreased by about 21% by quantity.

The report also highlighted concerns about the current $0.08 pass-through charge, which does not fully cover the cost of bags for retailers. The fee, required by law, will increase to 12 cents on Jan. 1, 2026.  Additionally, WSU found that consumers may not reuse heavier bags enough to offset their higher environmental costs, though no state-specific data on bag reuse was available.

Commerce and Ecology offcials emphasized limitations in the data. The agencies support maintaining the 2.25 mil plastic bag requirement and caution against returning to single-use 0.5 mil bags or moving to thicker 4 mil bags. They remain open to adjustments in the pass-through charge, provided “equity” and “environmental justice” concerns are addressed.