If you are filing a current year Form 1065, mark the appropriate name change box on the form: Page 1, Line G, Box 3. 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. You don't have to mail a special letter to the IRS to change your LLC name. Are you planning an IRS business name change? You may not need a new EIN. An IRS LLC name change is perhaps the easiest one to perform. All you need to do is put down a name change statement on your company's tax return. The namechange letter should clearly state that your business name has changed. Write to the IRS to inform them of the name change.