The parent receiving child support often also receives real tax benefits tied to the child — head-of-household status, the dependency exemption, the child tax credit, and the child care tax credit, if applicable. Depending on the case, these can add up to a few hundred dollars a month in value, and most state guideline formulas don’t account for them at all.
Every state’s guideline law allows a judge to deviate from the standard calculation for good reason, and the value of the other parent’s tax benefits can be one of those reasons — along with the amount of parenting time you actually have. These arguments require real numbers, not just the general principle: a tax professional can calculate the specific value in your case, and an economist or actuary can help quantify parenting-time costs if that’s part of your argument.
This is general information, not legal or financial advice — work with a family-law attorney and a tax professional to evaluate whether a deviation argument applies to your case.