Explain the problem. Print out a copy of this sample letter (PDF) for reference or download the Microsoft Word sample letter (DOCX) to change as needed and save to your computer.Consumer Action offers a sample complaint letter and an email complaint template. You can cut and paste these documents below. I am writing today to complain of the poor service I requested from your company on ______. Here are simple tips, templates and examples for writing good complaints letters. This approach to complaints letter-writing is effective for private consumers. First of all, you should write your complaint in details, and in good language. The basic rule is keep the letter short, punchy and clear, and preferably on one side of a sheet of paper. Take a look at this example complaint letter for ideas on how you should approach writing a letter of complaint.