How To Write A Letter Of Disagreenment To The Irs . The next paragraph should contain what is being challenged and why. Add some facts with your letter which will add to the credibility of the letter. 7+ Sample Disagreement Letters Writing Letters Formats & Examples from www.sampleletterword.com When writing a letter to the irs, those that are properly addressed will get routed to the correct department and get a quick response. Include any information that you believe would help verify taxes paid or the amount that was claimed on your. A statement that you want to appeal particular irs findings to the appeals.