Colorado Governor Jared Polis signed into law House Bill 21-1162,

the Plastic Pollution Reduction Act on July 6, 2021.   

Ban on single-use plastic shopping bags and Styrofoam food containers 

goes into effect in 2024 and does allow several exemptions including
restaurants and shops with three or fewer locations in the state.  

Shops that are not exempted, must start a 10-cent bag fee on paper and plastic bags
which goes in effect January, 2023.
Local governments may enact their own fees sooner and set their own regulations of

plastic and packaging products above and beyond what the state requires.

As of
July 1, 2021 Denver shoppers at all stores will be charged a 10-cent bag fee

if they don't bring their own bag with them. 

Wherever you shop, use your own re-usable shopping bag.
 Keep a few handy in your car.