2025 TurboTax assumes that dollar amount of your tax withholding will remain unchanged from 2024 and calculates the amount of estimated tax payments that guarantees that you would not be subject to an underpayment penalty regardless of how much your 2025 taxable income might differ from 2024. Because the total of the calculated 2025 estimated tax payments is greater than the balance due on your 2024 tax return, I suspect that NCperson's suggestion that your 2024 income could be high enough to trigger the 110% of 2024 tax liability threshold is a good guess. If so, that would suggest that your 2024 tax liability was somewhere around $32,000. (10% of $32,000 equals the difference between $6,000 and $9,200.)
A reasonable way to approach your 2025 estimated tax payments would be to pay the $2,300 for each of the first three tax quarters and then do at least a rough calculation of your 2025 tax liability by early January 2025 so that you can determine how must of a fourth-quarter estimated tax payment to make. However, if you have not already made estimated tax payments for the first two tax quarters, the payment dates for which have already passed, you might need to either increase tax withholding from sources of income instead or, if a large proportion of your income occurs late in the year, annualize income on Schedule AI of Form 2210, otherwise you might be subject to underpayment penalties for the first two tax quarters .
