What do you include in a debt collection letter? What should a request for payment letter include?This guide equips you with the strategies needed to enhance debt recovery efforts and safeguard your business's financial stability. You can document the previous interactions, formally offer to resolve the matter, and emphasize what you'll do if the demand isn't met—usually filing a lawsuit. How To Write A Formal Demand Letter For Payment And Money Owed To Clear Outstanding Debt? A demand letter is also called a debt collection letter. Money Owed Demand Letter – Strictly for debts or outstanding balances. To dispute a debt, you must write a letter to the debt-collection agency within 30 days of their initial contact with you. Provide a comprehensive breakdown of the outstanding balance, including the original invoice amount, service dates, and any additional charges. So I just left after completing my current work in hand and joined the new company.