Today, Walmart corporate offices announced masks will be required for all shoppers beginning July 20.

Walmart and Sam’s Club have required employees to wear masks since April.

In a corporate letter sent to all U.S.-based employees dated April 17 and signed by Walmart U.S. CEO/President John Furner and Sam’s Club CEO/President Kath McLay, the retail business announced it would “begin requiring that associates wear masks or other face coverings at work. This includes our stores, club, distribution and fulfillment centers, as well as in our corporate offices. We’ll also be encouraging customers and members to wear face coverings when they shop with us.”

Prior to this letter, face coverings for employees were optional. Beginning April 17, corporate policy made them mandatory.

Now that mandatory requirement will include all shoppers beginning with store openings Monday.

The letter acknowledges that wearing a mask does not guarantee a person will not contract the virus, but that it is a proper health precaution to take for one’s self and the sake of others.

“It’s important to remember that face coverings are simply an additional health precaution. They do not guarantee against the spread of this virus, and they do not replace the most important steps you can take to keep yourself and others safe: 6-20-100,” the letter reads. “Whether at work or elsewhere, practice six feet of social distancing whenever possible. Regularly wash your hands with soap for 20 seconds. And if you have a temperature of 100 degrees or higher, stay home.”