The desktop download software is already available, so if you need TurboTax Business for 2024 you can purchase and download it to a Windows PC and get started on your 2024 return, but understand that there will be many updates to the software. You cannot actually e-file a 2024 return until late January, when the IRS begins to accept 2024 returns.
You have not actually described your business, though---so we do not know if you need TT Business or if you just need online Premium to complete a return with a Schedule C. If you are a sole proprietor, you can also use any version of the desktop download in order to prepare a Schedule C.
Again....you cannot file a 2024 return until late January 2025 at the earliest.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
Most business returns are now able to be efiled, but there are some returns that contain forms that aren't available to file yet. Visit the following TurboTax help article to see if that is the case for any of the forms in your return.