Turbotax computed excess advance premium tax credit repayment alone ($0 from tax table) and no penalty for 2020 as I got a refund with 2019 taxes. However, I am very concerned about AGI (not modified AGI) estimation for 2021.
In addition to one year grace (or forgiveness) period, the percentile of underestimation of AGI or modified AGI probably matters for the assessment of tax penalty amount. However, in my particular example, I am considering the possibility of underpayment of taxes for two years in a row consecutively; one year could be due to underestimation of AGI followed by modified AGI second year (or vice versa). Though triggering events are different (AGI verses modified AGI), does IRS consider both simply as under-reporting of income and penalize anyway with 2nd year taxes (assuming avoided penalty with 1st year taxes due to grace period availability)?
