I used Turbotax to file my tax last year, but I received a notice from IRS that I underpaid. How did it happen? How can I prevent it this year?

There are a couple of ways that you might prevent an underpayment penalty for 2024.

• You can increase your workplace withholding on your W-4 form. You can complete a new 2024 W-4 form in the Other Tax Situations section and give to your employer.
• You can pay estimated taxes for 2024 based on what you owe for 2023. See this FAQ for how that is calculated in the same section.