If you are filing a current year Form 1065, mark the appropriate name change box on the form: Page 1, Line G, Box 3. Learn how to change your business name with the IRS.In order to change your LLC name with the IRS, you'll need to mail them a letter and show proof of the state approving your LLC name change. How do I fill this out? To fill out this form, you need to provide the old and new company names, your federal identification number, and contact details. The namechange letter should clearly state that your business name has changed. Yes, business owners and other authorized individuals can submit a name change for their business. Tried to report on IRS site, but I couldn't figure it out. It's not as scary as it sounds, I promise! Official website of the U.S. Social Security Administration.