This guide is for general information only and is not legal advice. Laws change — verify current rules with your state DOT or a licensed attorney before relying on this for any legal matter. Read full disclaimer.
The rule
Bicycles are permitted on Interstate highways in Wyoming. WYDOT expressly permits bicycle travel on the shoulders of all Wyoming Interstate highways (I-25, I-80 and I-90) — across most of the state the Interstate is the only paved through-route, and the policy reflects that geography. Specific tunnels and certain urban segments through Cheyenne and Casper are signed prohibited; consult WYDOT's bicycle-travel guidance for the current corridor list.
What this means in practice
Interstate cycling is legal in Wyoming, but ride only where you have a wide, clean shoulder and exit at the first signed bicycle exit when conditions deteriorate.