Sample
[DATE, ex. Wednesday, June 11, 2006]
[[NAME, COMPANY AND ADDRESS, ex.
Robert Brown
1234 First Street
Suite 567
Anycity, Anystate 85245]
Dear [NAME, ex. Robert Brown],
Enclosed is my rent check for [MONTH, ex. September].
I do understand this payment is late and I hope you will accept my apology. [BRIEFLY STATE REASON, ex. I was forced to take a late salary payment this month to slow business.] [MAKE REASSURING STATEMENT, ex. I am assured, nonetheless, that there should be no similar problems in the future.] You have my guarantee that this will not occur again.
Sincerely,
[YOUR NAME]