Trying to make sure I won't be subject to a penalty for underwithholding. When trying to figure out how much I need to withhold, it is 100%/110% of only federal income taxes, not social security or medicare, correct? Put another way, is it A or B:
A: 2020 federal income taxes withheld must be 110% more than 2019 federal income taxes.
or
B: Add together 2020 federal income taxes withheld, social security, and medicare. This number must be 110% of 2019 federal income taxes, social security, and medicare.
Thanks!
