California Child Support Arrears: How Interest Accrues and How to Collect It

California Child Support Recovery System | Justice Foundation

Unpaid child support in California doesn’t just sit idle — it accrues interest at 10% per year under California law, compounding on the principal arrears balance. If your children’s other parent has been delinquent for years, the total amount owed — principal plus accrued interest — may be substantially larger than you realize. Understanding how to calculate, document, and collect that interest is part of a complete arrears recovery strategy.

The 10% Interest Rule

California Family Code Section 4722 establishes that unpaid child support judgments accrue interest at 10% per annum. This rate applies automatically — you don’t need a court order to establish the interest obligation. The interest accrues on the principal arrears balance from the date each payment was due and unpaid. On a $30,000 arrears balance that has been outstanding for three years, accrued interest alone exceeds $9,000.

Unlike some states, California does not compound interest on child support arrears — the 10% applies to the principal balance, not to previously accrued interest. But on large arrears balances outstanding for extended periods, the total interest obligation is still substantial and fully collectible through the same enforcement mechanisms that apply to the principal.

How to Calculate Your Arrears Balance

The official arrears balance is maintained by DCSS if you have an open DCSS case, or can be calculated independently using payment records and court orders. For each month a payment was missed or short, note the amount owed, the amount received (if any), and the date the shortfall became final. The arrears balance on any given date is the sum of all shortfalls minus all payments received since the order was entered.

Interest is calculated separately for each installment from the date it was due. For a large arrears balance with a complex payment history, a spreadsheet calculation or assistance from DCSS is the most reliable approach. The Justice Foundation kit includes an arrears and interest calculation worksheet.

Collecting Interest Along With Principal

All enforcement mechanisms available for principal arrears — income withholding, bank levies, property liens, tax intercepts — apply equally to accrued interest. When DCSS or a court issues an enforcement order, it should specify the total amount owed including principal and interest as of the calculation date. Ensure your enforcement demand includes the interest calculation — enforcement agencies don’t automatically add it unless you provide the calculation.

Statute of Limitations on Arrears

California child support arrears do not have a short statute of limitations — unpaid support is enforceable for 10 years from the date each installment became due, with the ability to renew judgments. This means even very old arrears remain collectible. If the paying parent has recently come into income, assets, or inheritance, old arrears that seemed uncollectable may now be worth pursuing aggressively.