Business codes setup and used by the IRS for statistical purposes to categorize your business. The code you enter will not affect the outcome of your tax return
This information is usually entered in the business section of TurboTax in the Enter Your Business Code screen.
Click the Lookup Business Codes button, enter some keywords that describe your business (e.g., day care, bookkeeping, door-to-door, etc.), and then click Search.
The code for Real Estate Agents: 531210 (Offices of real estate agents & brokers)