I purchased a business on 12/26/18, the transfer of the business didn't occur until 1/1/19. How do I account for this in 2018 on my personal taxes?

[IreneS]

Since the business really wasn't yours to run in 2018, you don't have to enter it on your 2018 return.

If you will be running it as a sole proprietor you will report the income and expenses on a Schedule C in your 2019 return.  To do this you will need either TurboTax Self-Employed (online) or TurboTax Home & Business (CD/download).

Good luck with the business!