1234, Main Street
Boston, MA 02123
04 April, 2005
<Recipient Address Goes Here>
Re: Account No. <account number>
This is to inform you that your account with us is now [number of days] days past due.
As it was intimated to you repeatedly through previous correspondences, we have not received any payment from you.
Now, we are informing you once again that if your payment for the amount of [$ ??] is not received within [no. of days] from this notice, then a negative report will be sent to [name of credit bureau] stating that this account in under delinquent status.
Thus, if you want to keep your good credit rating, please arrange your payment immediately. And, if you are unable to make payment at this time for any reason, please contact us so that we can work out a payment plan as per your convenience.
Thank you for your immediate attention regarding this mater. We look forward to hear from you soon.
encl: <List of enclosed items goes here>