Anticipating child support costs can be intimidating and complicated. Whether you’re the primary caregiver or the parent who will be paying child support, getting the information you need to budget and plan can feel impossible. Every case is different, and every child and family is different, but you can do some simple calculations to get an idea of what to expect. Guideline Child Support There are some misconceptions about the “guideline” child support described in the Texas Family Code. This refers to the specific percentage of the paying parent’s income that will be paid in child support each month. This isn’t guaranteed to be the exact number, but a baseline. How much is this percentage? That depends on how many children a parent is supporting. The percentage starts at 20% and goes up 5% for each additional child.