Underpayment Penalty

Yes.  By default, the IRS considers income to be evenly earned throughout the year, even if it is not. So for a ump sum of income paid between January 1 and March 31, 2024, you can either:

Make an estimated tax payment by April 15

or

Split up your estimated payment into 4 installments and pay them before April 15, June 15, September 15, and January 15 next year.

Depending on your other income, your total estimated payment is likely to be about $12,500.  If you over-pay, you will get the difference back as part of your refund.

And don't forget you probably need to make state estimated payments, too. 

Yes, you would be wise to make the estimated payments.

Open Tax Tools

1. On the drop-down select Tools
2. There will be 4 green boxes
3. Select Topics Search
4. Type the Estimated taxes paid for next year
5. The first screen will be Enter Your 2024 W-2 Wage Information
6. Answer the questions and enter amount.
7. You will come to Enter 2024 Other Income
8. Follow the interview and enter income & deductions.
9. You will come to Other Income
10. Put the $50K in here.

TurboTax will guide you through the mailing process for your 1040-ES estimated payments.

Or you can setup an account and pat directly to the IRS Direct Pay With Bank Account