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stock grant, taxes, and the irs
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i went through this too. there's a safe-harbor provision. if you prepay as estimated tax payments, 110% of your previous year's tax liability, there's no penalty for underpayment of the big liquidity-event tax liability.  https://www.irs.gov/publications/p17/ch04.html that's with the feds. your state may have different rules. you would be very wise indeed to hire an accountant to prepare your return this year. if i were you i'd ask your company's cfo or finance chief to suggest somebody.   congratulations, by the way.
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