USMS holds five long distance postal championships each year: the One Hour, 5K, 10K, 3000 yd. and 6000 yd. events. Swimmers who complete all five championships in the same year will be sent a participation patch to honor their achievement.

Results for the postal series challenge are available here:

• 2011 Results
• 2010 Results
• 2009 Results
• 2008 Results
• 2007 Results
• 2006 Results
• 2005 Results
• 2004 Results
• 2003 Results