Sample friendly reminder letter to customer regarding dues

Dear Sir,

This is intended merely as a friendly reminder of your past-due account of Rs. ____________________ which we believe you have overlooked. Now that it has been brought to your attention, we are sure you will want to bring your account up-to-date.

If by chance your cheque is already in the mail, please disregard this reminder and accept our thanks.

Thanking you

Sincerely yours

(Name)