Do I need to make an estimated tax payment after getting a large sum from the sale of stock where taxes were not withheld if my withheld taxes cover the previous year's?

[bluedeb]

Do I need to pay estimated taxes?

That depends on your situation. The rule is that you must pay your taxes as you go.

If at filing time, you have not paid enough income taxes through withholding or quarterly estimated payments, you may have to pay a penalty for underpayment.

To determine whether you need to make quarterly estimates, answer these questions:

1. Do you expect to owe less than $1,000 in taxes for the tax year after subtracting your federal income tax withholding from the total amount of tax you expect to owe this year? If so, you're safe—you don't need to make estimated tax payments.
2. Do you expect your federal income tax withholding (plus any estimated taxes paid on time) to amount to at least 90 percent of the total tax that you will owe for this tax year? If so, then you're in the clear, and you don't need to make estimated tax payments.
3. Do you expect that your income tax withholding will be at least 100 percent of the total tax on your previous year's return? Or, if your adjusted gross income (Form 1040, line 37) on your tax return was over $150,000 ($75,000 if you're married and file separately), do you expect that your income tax withholding will be at least 110 percent of the total tax you owed for the previous year? If so, then you're not required to make estimated tax payments.

If you answered "no" to all of these questions, you must make estimated tax payments using Form 1040-ES. To avoid a penalty, your total tax payments (estimated taxes plus withholding) during the year must satisfy one of the requirements we just covered.

Also see the following:

https://turbotax.intuit.com/tax-tips/small-business-taxes/estimated-taxes-common-questions/L1luHqVdl