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.The first step is to file a form called the Articles of Amendment with the Department of State and wait for it to be approved. 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. , which was registered on. Changing the name of a Florida business requires a couple steps, including reaching out to the Secretary of State and the IRS. Register their "fictitious name" or "dba" name with the Florida Department of State prior to conducting business in Florida. FOR FICTiTIOUS NAME OR OWNERSHIP CHANGE COMPLETE SECTIONS 1. Mol. Partial names, such as Doe, J for John A. Doe, are acceptable.