Wyoming law prohibits any person from consuming or possessing an alcoholic beverage in a vehicle if:
This restriction applies to all persons within the car—including the driver and passengers—and to any vehicle located on public highways.
Alcoholic Beverage. Wyoming defines "alcoholic beverage" to include any spirituous or fermented fluid intended for beverage purposes of at least .5% alcohol by volume. So, some non-alcoholic beers and mixers as well as things like alcohol-based, liquid-filled candles may be permitted.
Certain vehicles. Wyoming's open container law isn't applicable to passengers riding in certain types of vehicles used primarily for the transportation of passengers for compensation. Passengers inside these vehicles are permitted to possess and consume alcohol, but the beverage must not be within the driver's zone of control.
Areas of the vehicle. Wyoming's open container laws are intended to apply to the passenger areas of the vehicle. The open container restrictions aren't applicable to items in the trunk of the car, bed of a pickup truck, or behind the back seat (if the car doesn't have a trunk) as long as they are not readily accessible to the driver or passengers. Open containers may also be securely stored in the cabinets of a recreational vehicle (a vehicle with plumbing) but cannot be accessible to the driver or passengers.
Restaurant Wine. Wyoming does authorize the transportation of a partially-removed alcoholic beverage after dining at a restaurant. However, the bottle must be resealed by the restaurant and placed in a tamper-proof bag with a dated receipt.
A first-offense open container conviction in Wyoming will result in a fine of up to $200 but no jail time. However, a second conviction within the same year can result in fines of up to $300 and a maximum 30 days in jail. A third or subsequent conviction within a year will result in a fine of up to $500 and a maximum six months in jail.