[DATE, ex. Monday, March 31, 2008]

[NAME, COMPANY AND ADDRESS, ex.
Link Building
1234 First Street
Suite 567
Anycity, Anystate  85245]

Dear [NAME, ex. Link Building],

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, ex. Jill Jones]