Quick answer: In New Hampshire, each support payment is a judgment when due, with a lien on property for arrears and simple interest at the state treasurer’s annual rate. An income assignment adds at least 20% of current support toward arrears, and a license can be certified at 60 days in arrears in department cases.
This New Hampshire child support arrears calculator adds up the unpaid installments and simple interest at the rate you enter under RSA 336:1, and flags the 60-day, 20% and passport thresholds. The judgment rate changes every January 1, so enter the rate that applies.
New Hampshire child support arrears and interest at a glance
| Rule | What New Hampshire says |
|---|---|
| Judgment | All support payments ordered or administered by the court are deemed judgments when due and payable (RSA 461-A:14, VI) |
| Lien | Arises by operation of law on real and personal property for arrears and includes future unpaid support (461-A:14, VII) |
| Interest | Annual simple rate on judgments: 26-week T-bill discount rate plus 2 points, set yearly by the state treasurer (RSA 336:1, II) |
| Income assignment | Current support plus at least 20% of it toward arrears, within federal limits (RSA 458-B:4, III-IV) |
| Licenses | Not in compliance at 60 or more days in arrears (department cases); 21 days after notice before certification (161-B:2, III; 161-B:11) |
| Arrears and modification | Not altered by a modification for periods before the motion was filed (461-A:14, VIII) |
How do child support arrears work in New Hampshire?
- Interest and method. See the New Hampshire child support interest rate.
- Collection. See what happens if you do not pay child support in New Hampshire.
- Whether arrears can be changed. See whether New Hampshire child support arrears can be changed.
What does this arrears calculator check?
You enter the monthly support, the number of installments unpaid and the annual rate. The calculator adds simple interest from each due date and flags the judgment, the 60-day license trigger in department cases, the 20% add-on in an income assignment and the $2,500 passport line. It does not model partial payments. To change the amount going forward, see the New Hampshire child support modification calculator, and for when the obligation stops, the New Hampshire child support end date calculator.
Frequently asked questions
Does New Hampshire charge interest on child support arrears?
Support payments are judgments when due, and judgments carry simple interest at the state treasurer's annual rate. The department may waive interest on support debt owed to it.
What is the New Hampshire judgment interest rate?
The 26-week Treasury bill discount rate at the last auction before September 30, plus 2 percentage points, rounded to the nearest tenth, in effect January 1 to December 31 of the following year.
Is New Hampshire judgment interest compound?
No. The statute says the annual rate is a simple rate.
How much extra does New Hampshire withhold for arrears?
At least 20% of the current support, unless the arrears are smaller, within the federal limits.
When can a New Hampshire license be certified for unpaid child support?
When the obligor is not in compliance, which includes being 60 or more days in arrears on support payable through the department, after a 21-day notice.
Official sources
- RSA 461-A:14: support; judgments; liens; arrears
- RSA 336:1: rate of interest
- RSA 161-C:23: interest on support debt owed to the department
- RSA 458-B:4: amount withheld
- RSA 161-B:2: definitions, including compliance
- RSA 161-B:11: revocation and denial of licenses
- 15 U.S.C. 1673: restriction on garnishment
- 42 U.S.C. 652(k): denial of passports