To start a case for money, the plaintiff fills out forms called a Summons and a Complaint, or a Summons with Notice. We'll walk you through how to write a demand letter for payment below, with sample demand payment letters and tips for professional, effective messaging.Use this letter to ask a customer to pay the money that they owe you. Put your business letterhead at the top of the letter. 1. What size debt are you prepared to recover? This Part shall be applicable to civil actions and proceedings in the Supreme Court and the County Court. The first step to any debt recovery process for a credit manager is the serving of a letter of demand upon a debtor individual or company. We've created ready-to-use collection letter templates. Read on below to find out what every letter should say in order to collect payment as soon as possible. We hope this letter finds you well.