Safe harbor for W-2 employee getting 1099

Hey Guys,

I need some help on understanding the safe harbor rules for individuals. I am a w-2 employee but just got a sizeable 1099 payment. Of course, no withholdings. I want to pay the tax by the IRS deadline (4/15/26) but wanted to make sure I am not going to get dinged on underpayment (or any other) penalties.

To use the safe harbor, all my W-2 withholdings have to be above line 16 from my 2024 return times 1.1? The way my withholding is set up, I am going to be above that by $200, so cutting close.

Are there any exceptions if it is a 1099 payment or anything else I am missing?

Appreciate the help!