Child Support Cap Increases- effective September 1, 2013 the child support cap for applying the guidelines increases from $7500.00 to $8550.00. Meaning that under the guidelines when calculating child support the person paying child support who earns $8550.00 or more net a month could expect to pay $1710.00 a month for one child, $2,137.50 a month for two children, $2,565.00 a month for three children and $2992.50 a month for four children under the guidelines.