[Your letterhead, if desired; if not, your return address]
[Date of letter—month, day, and year]
[Recipient's first and last names]
[Street or P.O. box address]
[City, State ZIP code]
Dear [recipient's name]:
I am writing regarding my account with your company, which is account number 9898 8988 8989. My payment of $100 was due to your company on December 8, and I apologize that you have not received it yet. I plan to send this payment for $100 on December 28. The payment is late because I have had some unexpected and sudden large medical bills for a serious condition. Also, my income has decreased recently, and this has put a strain on my ability to meet this financial obligation with you.
Thank you for your attention to this matter, and again, I apologize for this payment delay.
[Sender's first and last names]