Federal Module -- Form 2210 Schedule AI -- Wrong form or line

TurboTax's Schedule AI Line 14 calculation for columns (a), (b), and (c) fails to correctly apply the annualization scaling factor to both capital gains and qualified dividends when computing tax via the Qualified Dividends and Capital Gain Tax Worksheet; per IRS Publication 505 Worksheet 2-8, both capital gains and qualified dividends must be scaled by the same annualization multiplier (4x, 2.4x, and 1.5x for periods a, b, and c respectively) before computing tax for each period. TurboTax applies the annualization factor inconsistently — scaling qualified dividends but not long-term capital gains — resulting in an understated tax benefit and an overstated annualized tax liability, which in turn generates a false underpayment penalty on Form 2210 Line 19 where none would be owed under the correct calculation.

A self-employed business owner with variable income who uses the annualized installment method to avoid estimated tax penalties may be incorrectly assessed an underpayment penalty on Form 2210 Line 19 — requiring them to either pay a penalty they do not legally owe or invest significant time manually overriding TurboTax calculations using IRS Pub 505 Worksheet 2-8 spreadsheets.