Based on Texas Family Code Chapter 154
Texas lowers the percentage if you are legally responsible for other children not part of this court case.
Texas uses a simplified Percentage of Income model. Unlike most states that use "Income Shares" (counting both parents' income), Texas primarily looks at the Net Monthly Resources of the paying parent (Obligor).
If the paying parent is also legally responsible for other children (e.g., from a different marriage), Texas law requires a credit. This lowers the percentage applied to the current case.
For example, if you are paying for 1 child in court, but you have another child at home you support, your rate drops from 20% to 17.5%.
Net Resources is your Gross Income minus Federal Income Tax (for a single person), Social Security taxes, Medicare taxes, and the cost of health insurance for the child. It does not include deductions for 401k or voluntary expenses.
Yes. All wage and salary income, including overtime, tips, bonuses, and commissions, is included in Gross Income.