Thanks for the input. Because I have earned 95% of my income already this year and now unemployed / early retired I will not have any further witholding. I believe I need to use the Annualized Income method (AIM) to calculate my tax liability based on the income I've actually received up to the end of each payment period otherwise I may face a penalty for underpayment if I spread it evenly over the next 3 estimated payments. Turbotax doesn't seem to have anything except the estimator that allows me to pay in 3 installments which I would certainly prefer to do but I don't want to get penalized either. The annualized estimated tax worksheet is in publication 505. Publication 505 (2025), Tax Withholding and Estimated Tax | Internal Revenue Service
