How often can 5 Fridays 5 Saturdays and 5 Sundays occur in a single month?

One out of every twelve months is like that, so the average frequency is once per year. Most years have one such month. Years that end on a Monday don't have any, and years that begin on a Friday have two each.

These are all the occurrances during the first quarter of the 21st century:

• March 2002
• August 2003
• October 2004
• July 2005
• December 2006
• August 2008
• May 2009
• January 2010
• October 2010
• July 2011
• March 2013
• August 2014
• May 2015
• January 2016
• July 2016
• December 2017
• March 2019
• May 2020
• January 2021
• October 2021
• July 2022
• December 2023
• March 2024
• August 2025