how can I prevent the underpayment penalty?

[ThomasM125]

In general, you need to pay in 100% of the tax amount on your previous year tax return or 90% of the tax on your current year tax return on a quarterly basis to prevent a penalty for underpayment of tax. If your income is over $150,000  or $75,000 if married filing separate, you must pay in 110% of the previous year income tax. You can learn more by reading this TurboTax article.

[fanfare]

Clarification:  the above rule applies only when the amount paid comes from withholding alone.

Otherwise, make Estimated Tax paymnents.

@stollefam