"...Memorial Day, a federal holiday to remember the men and women who died while serving in the armed forces, is Monday, May 29. Facilities that are open on the holiday must fly the U.S. flag at half-staff. The U.S. flag must be flown at half-staff from sunrise — or the hour when it’s raised — until noon. Then, hoist the flag to the peak of the staff, where it either must fly until the time of closing or no later than sunset (unless the flag is lighted). When the U.S. flag is flown at half-staff, all other flags must fly at half-staff, too. ..."
Reference: usps.com
