2024 TurboTax Home & Business Windows calculated that I owe about a $600 penalty in underpayment of California tax if I pay on April 15, 2025 or about $100 if I pay on February 15, 2025. By my calculations, I don't owe a penalty because I qualify for the Safe Harbor rule of paying 110% of the prior year's tax in withholding and estimated tax. I examined the worksheet that TurboTax filled out, and it doesn't seem to include my estimated tax payments. It only asked for the amount of my withholding. Therefore, it says I don't qualify for the Safe Harbor rule. This looks like a bug to me. My solution is to not have TurboTax calculate the penalty and let the State of California calculate the penalty. I will file as soon as possible to minimize any possible accrual of interest penalties. And no, I do not want to upload my tax return to have Intuit TurboTax people look at it. I couldn't find anywhere on the website to report bugs, unless I actually suffer a loss due to the bug.
