The other way to start the appeals process is by filing a petition with the US Tax Court. If you do not respond to the determination letter a statutory notice of deficiency is issued. When you receive a notice of deficiency, you have 90 days to file a petition with the tax court, or you lose your right to appeal. (There are other avenues to pursue if you miss this deadline, but it make the process more difficult.) After you file the petition, your case will be sent to appeals.
IRS appeals is a separate and independent branch of the IRS that is separate from the examinations (audit) division. The best description of them is they act as a mediator for the IRS. While, it is there goal to find in favor of the government, more often than not, if you make a reasonable argument, they will make a sound decision. This is contrary to the examination division, which in my experience, has the main goal of maximizing revenue for the government.
Appeals is where most cases are resolved and the best results are achieved. To start the appeal, read the determination letter and write a letter based on the issues you want to argue. When you file the appeal, the appeal's officer will then send you a letter requesting additional information related to your argument and for you to make any additional arguments. A conference with the appeals officer will be scheduled and a new determination letter will be issued based on the result of the conference and information provided. If the result is unfavorable, you can request a conference with a manager or file/proceed with a federal or tax court case.
If you have any questions please contact me directly or leave a comment.
As with everything related to the IRS, it is difficult to provide comprehensive information related to taxes and tax law on the web. Please do not rely on this article without consulting your tax professional.