I just noticed that my 2020 return includes a form 1040-ES to pay estimated taxes for 2021... but I am an employee. Do I have to pay these? I had almost a $0 refund

No, these estimates are optional. You may want to increase your withholdings to assure enough tax is paid in through the year. If the balance due is more than $1,000, you may be subject to penalties and interest.

No penalties or interest will be charged as long as you meet the withholding requirements described below:

• The IRS requires taxpayers to pay tax as the income is earned, either 100% of the prior year tax or 90% of the current year tax to avoid penalties and interest. (For taxpayers with adjusted gross income greater than $150,000, these percentages are 110% and 100%, respectively)

To calculate how much, if anything should be adjusted for your 2021 withholding, follow these steps inside TurboTax:

• Inside TurboTax, if you have not filed yet, enter W4 in the search box. Select the Jump to link in the search results and complete the interview.

For more information, see: How do I update my 2021 withholdings and print a new W-4?