Q3 Estimated Tax Is Due September 15 – Let the Safe Harbor Set the Amount

If you’ll owe the IRS $1,000 or more after withholding this year, your third estimated payment is due September 15. Don’t guess the amount. Pay a quarter of last year’s total tax each installment, 110% of that if last year’s adjusted gross income topped $150,000, and the underpayment penalty can’t touch you whatever this year earns.

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