How Child Support Is Calculated in South Carolina
South Carolina calculates child support using the South Carolina Child Support Guidelines. Unlike property division or alimony, where a judge weighs a list of factors, child support starts from a formula. The calculation begins with both parents' incomes and the number of children, accounts for overnights in some cases, and then adjusts for a short list of specific items.
In most cases, that means you can get a reasonable estimate before you file. But the formula is only as reliable as the numbers that go into it, and a few situations fall outside the standard calculation.
The core inputs
The guidelines use what is called an income shares model. The idea is that children should receive the same share of their parents' combined income that they would have received if the parents lived together. The guidelines add both parents' incomes together, find a basic support amount for that combined income and number of children, and divide that amount between the parents based on each parent's share of the combined income.
Income means gross monthly income, before taxes, and it is defined broadly. It includes wages, overtime, bonuses, commissions, self-employment income, rental income, Social Security benefits, unemployment benefits, and alimony, among other sources. If a parent is voluntarily unemployed or earning less than they reasonably could, the court can base support on what that parent could earn instead of what they actually earn. This is called imputing income.
Overnights matter once both parents have substantial time. When each parent has more than 109 court-ordered overnights a year and both parents share in the children's expenses, the guidelines provide a shared-parenting calculation that usually lowers the support amount, phasing in fully at 128 overnights. The judge decides whether to apply it, and overnights are counted across a full year, not a single month or summer. Equal time does not automatically mean no support. When incomes differ, the higher-earning parent often still pays.
The common adjustments
Some items are added to the basic support amount and shared between the parents in proportion to their incomes. These include the portion of health insurance premiums that covers the children, work-related child care costs, reduced to account for the child care tax credit, and extraordinary medical expenses that are regular and predictable, such as ongoing counseling.
Other items reduce a parent's income before the calculation. Alimony between the parents is subtracted from the paying parent's income and added to the receiving parent's income. Child support or alimony a parent already pays under an earlier court order is subtracted, and a parent receives a credit for their other biological or adopted children living in their home.
The basic support amount already assumes the parent receiving support covers the first $250 per child per year in routine uninsured medical costs, like co-pays and over-the-counter medicine. Reasonable and necessary uninsured costs above that are generally split between the parents in proportion to their incomes.
These adjustments can move the number meaningfully, which is why two families with similar incomes can land at different support figures.
Where the standard formula stops
If the parents' combined gross income is below $750 a month, there is no formula figure. The court sets support case by case, ordinarily at no less than $100 a month. If combined income is above $40,000 a month, the schedule ends and the court again decides case by case.
If each parent has primary custody of at least one of the children, the guidelines use a separate split-custody calculation. The guidelines also protect a minimum level of income for a low-income paying parent, which changes the calculation at the lower end of the schedule.
When the number can differ from the guideline
The guideline amount is presumed to be the correct amount of support. A judge can order a different amount, called a deviation, but deviation is the exception rather than the rule. When the amount ordered differs significantly from the guideline figure, the judge must make written findings stating what the guidelines would have required and why a different amount is appropriate.
Recognized reasons for deviation include private school or college expenses, extraordinary travel costs for court-ordered visitation, a substantial difference between the parents' incomes, significant income of the child, how the parents' property and debts are divided, certain types of alimony, and families with more than six children.
If you and the other parent agree on a different amount
Parents can agree to an amount that differs from the guidelines, and that is common in uncontested cases. But an agreement does not bind the judge on its own. The court can approve a deviation based on an agreement if both parents have lawyers, or, if a parent does not have a lawyer, after the judge questions that parent and is satisfied they fully understand what they are agreeing to.
Even then, the judge has an independent duty to decide whether the amount is reasonable and in the children's best interest. If you are agreeing to no child support, or to an amount well below the guideline figure, expect the judge to ask why.
Estimate your number, then confirm the details
For most families, the guidelines make a solid estimate possible. Our Child Support Calculator is built on the 2024 South Carolina Child Support Guidelines, November 2024 edition. You enter each parent's gross monthly income, the number of children, overnights, and the children's health insurance and work-related child care costs, and it produces an estimate for combined incomes between $750 and $40,000 a month.
The calculator does not account for alimony between the parents, support or alimony paid under a prior court order, extraordinary medical expenses, other children a parent supports, or split custody. If any of those apply, or if either parent's income is uncertain or likely to be disputed, treat the result as a starting point rather than a final figure.
If your divorce involves minor children, the process and paperwork differ from a case without children. Our with-children divorce packet is designed for parents who agree on custody, parenting time, and support.
Christopher J. Archer
Licensed South Carolina attorney (SC Bar #101662)
USC School of Law
Archer Swearingen Family Law, LLC
This post is general information about South Carolina family law, not legal advice. Every case is different. If you have questions about your specific situation, consider speaking with a South Carolina family law attorney.