We offer several ways for you to obtain Maryland tax forms, booklets and instructions. You can also file your Maryland return electronically online.Every Maryland corporation must file a corporation income tax return, using Form 500, even if the corporation has no taxable income or is inactive. To start a Maryland S corporation, you'll need to create either a limited liability company (LLC) or a C corporation if you haven't already done so. Step 1: Choose a name for your corporation. The name must have a corporate ending, such as Corp. Find the information you need to incorporate your business in Maryland.