Retroactive Child Support Adjustment

When a court modifies a child support order, the modification is usually effective from the date the motion to modify was filed. The time between the filing date and the court order creates an overpayment or underpayment that needs to be adjusted. This calculator determines the adjustment and spreads it over a chosen number of months.

Enter the following information:

• The child support amount before the adjustment.
• The child support amount after the adjustment.
• The date the motion to modify was filed.
• The date of the court order.
• The number of months to spread the adjustment over.
• Whether to round the number of pending months up or down.

The results show the Adjusted Child Support, the Adjustment Per Pay Period, the Total Adjustment, and the number of Months Pending.

If the support amount decreased, the payer overpaid during the pending months, and the adjustment per pay period is subtracted from the new amount for the duration of the adjustment. If the support amount increased, the payer underpaid, and the adjustment is added to the new amount.