My wife is a new M.D. She is working for a hospital and charges by the hour. She gets paid once per month and gets the gross amount of her paycheck. No deductions. How much should she set aside from each paycheck and what type of taxes does she need to pay (CA). Our tax bracket is in the 6 figures. I am not self employed. Should she pay quarterly so they dont add up? She was told a big mistake new doctors make is they spend the whole paycheck and end up owing much at the end of the year which they dont have.