What do you include in a debt collection letter? 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. Fill in your information on the template letter and edit it as needed to fit your situation. 3. Print and mail the letter. Have you recently settled a debt and are searching for a paid in full letter? Good news, we've got two free sample form letters below. Brooks Rehabilitation is celebrating 50 years of caring in 2020. Throughout the year, we'll be sharing 50 Stories for 50 Years. Fill in your contact details, the account number and any extra information you want to include in the grey shaded areas.