Wife made an IRA to Roth IRA conversion last December which greatly increased our income, therefore we made an estimated tax payment to cover the tax withholding shortfall on Jan 17, 2023. That payment amount was based on IRS guidance for greater than $150K AGI (the lesser of 110% of last year's tax liability OR 90% of the current year's liability).
For 2022, our tax liability with the conversion was $30,022. Our withholdings totaled $10,244. I elected to use the 110% of last year's tax as that was a known. I arrived at the estimated payment amount by taking the 110% of last year and subtracting what was withheld during the year resulting in $21,290 as the payment made. Even with this approach, an underpayment is being calculated by TT even though a refund is final result. Where did I error in understanding the guidance from the IRS? And is TT calculating correctly?
