Ten Percent Interest: How Arrears Grow While Deadbeats Wait

Every unpaid support installment starts earning 10 percent simple interest the day it is missed. Time, for once, works for the custodial parent — and the compounding total is your settlement leverage.

What California Law Says

Support arrears bear interest at the legal judgment rate of 10 percent per year, accruing on each installment from its due date. Payments apply to current support, then interest, then principal — a sequence that keeps balances alive against partial payers — and the interest is as collectible as the base.

How to Collect, Step by Step

1. Compute interest installment by installment — each missed month has its own start date.
2. Use the DCSS audit or the kit’s calculator to produce a defensible running balance.
3. Include the interest figure in every demand and filing; payors negotiating against the full number behave differently.
4. Understand the application order when he pays partially — principal shrinks last.
5. Leverage the growth curve in lump-sum talks: your discount today trades against guaranteed 10 percent tomorrow.

Common Questions

He owes 40,000 in missed payments from the last decade. What is the real balance?

Substantially more — a decade of 10 percent on staggered installments commonly adds half again or more; run the audit before naming any number.

Can a judge waive the interest to encourage him to pay?

Accrued interest is part of the judgment and not subject to retroactive forgiveness — negotiated settlements are the lawful path to any discount, and they are yours to accept or refuse.