West Virginia's House has voted 85-14 to let employees bring loaded guns to their workplaces as long as they are locked in their cars.
The bill, titled the "Business Liability Protection Act," now goes to the Senate.
Supporters say it would expand Second Amendment rights.
Critics say it makes workplaces more dangerous and West Virginia less attractive to companies that want to control their premises.
It says the owner or manager of a property cannot prohibit any customer, employee or invitee from having a legally owned gun in its parking lot provided the weapon is inside a locked vehicle or compartment.
They would be prohibited from asking whether anyone has a gun locked in their car or truck.
Violations would be subject to civil penalties up to $5,000.