Thanks for the comment.
but I'm still confused because FTB's instruction says as follows.
My AGI in both prior year and current year were over $150,000, I should have withheld 110% of prior year tax liability to avoid penalty.
The following is copied from FTB's instruction fore Form 540
https://www.ftb.ca.gov/forms/2020/2020-540-booklet.html
Line 113 – Underpayment of Estimated Tax
You may be subject to an estimated tax penalty if any of the following is true:
- Your withholding and credits are less than 90% of your current tax year liability.
- Your withholding and credits are less than 100% of your prior year tax liability (110% if AGI is more than $150,000 or $75,000 if married/RDP filing separately).
- You did not pay enough through withholding to keep the amount you owe with your tax return under $500 ($250 if married/RDP filing separately).
- You did not make the required estimate payments, if you pay an installment after the date it is due, or if you underpay any installment, a penalty may be assessed on the portion of estimated tax that was underpaid from the due date of the installment to the date of payment or the due date of your return, whichever is earlier. Get the 2020 form FTB 5805, Underpayment of Estimated Tax by Individuals and Fiduciaries, for more information.
