US retail giant Target has asked customers not to bring guns into its stores, after Texas gun rights activists demonstrated in a Texas shop with rifles slung over their shoulders.
CEO John Mulligan said guns were at odds with its family atmosphere.
Many US states allow people to carry guns in some fashion, but businesses may ban them.
Gun control activists applauded the new rule, coming as many states loosen laws restricting the carrying of firearms.
"[We] respectfully request that guests not bring firearms to Target - even in communities where it is permitted by law," Target CEO John Mulligan wrote in a statement on the company's corporate blog.
"We've listened carefully to the nuances of this debate and respect the protected rights of everyone involved," he added. "Our approach has always been to follow local laws, and of course, we will continue to do so.'Horrified'
"Bringing firearms to Target creates an environment that is at odds with the family-friendly shopping and work experience we strive to create."
Target - which operates more than 1,700 stores in the US - now joins fellow large retail chains Starbucks and Chipotle in disallowing guns inside their establishments.
National advocacy group Moms Demand Action applauded the decision on Wednesday, noting it had gathered 400,000 signatures on a petition to persuade Target to ban guns.
"Moms everywhere were horrified to see images of people carrying loaded assault rifles down the same aisles where we shop for diapers and toys," Shannon Watts, the group's founder wrote in a statement.
"Target recognised that moms are a powerful customer base and political force - and you can respect the Second Amendment and the safety of customers at the same time."
Ms Watts was referring to a clause in the US constitution that gun rights activists say limits the government's authority to restrict firearms.
In mid-June, members of a group called Open Carry Texas demonstrated with rifles in a Dallas-area Target, garnering a rebuke from the National Rifle Association for their tactics.
US President Barack Obama has proposed several federal gun control measures in recent years - including tightening the background check system to make it harder for convicted criminals to buy guns - but Congress has declined to act under pressure from the powerful gun lobby.
Meanwhile, on Tuesday a Georgia law - known to detractors as the "Guns Everywhere law" - took effect that dramatically expands the locations in which people may carry guns in public. Those include pubs unless otherwise expressly banned by the proprietors, churches, unsecured areas of airports, and government buildings.