[header] How to write a demand letter for debt collection [title] Address and date your letter. [step] You want to use a standard business format for your letter, addressing it to the individual or business that owes you money. Choose the date carefully to match the date you plan to send it-in other words, if you can't mail the letter until tomorrow, use tomorrow's date. 
[substeps] If you're addressing the letter to a business, typically you want to address the letter to your key contact with the company. When in doubt, call the company and ask to whom you should send a letter for debt collection.