File online- Save paper, save time, start your business online. 1. First, register with the Ohio Secretary of State.Registration information as well as forms are available online(opens in a new window) or at (877) SOS-FILE. Ohio Business Filings Portal. Start or maintain your Ohio business online. The 1st Stop Business Connection provides free statelevel information needed to get started or continue on your entrepreneurial journey. INCOME TAX FORM: Complete and return the Business Registration Form 48 to RITA. Keep the date(s) sheet for your records. 6. In Ohio, the business forms available are sole proprietorship, partnership, corporation, and limited liability company. In this guide, you'll find information on naming your corporation, getting a Statutory Agent, the fees you'll need to pay, business taxes and much more.