Interest on Child Support Arrears in Massachusetts: Rate, Simple vs. Compound and When It Applies

By the FigureMyTax Editorial Team · How we calculate

Massachusetts child support interest in DOR cases is stated as 0.5% a month plus a 0.5% monthly penalty, and the IV-D agency may set both by regulation. Each unpaid installment is already a judgment and a lien.

Does Massachusetts charge interest on child support arrears?

The IV-D agency may provide by regulation for the assessment of interest and penalties (G.L. c. 119A, s. 6(a)), and the Department of Revenue states that it imposes 0.5% interest and 0.5% penalties on all past-due child support monthly (DOR information sheet). The same chapter provides that interest collected goes to the individual obligee on whose behalf it was collected (c. 119A, s. 2). The rate for a private order that DOR is not enforcing is not stated in the sections we read.

What is 0.5% a month in a year?

6% a year before any compounding. The Massachusetts arrears calculator uses simple interest on each weekly installment from its due date at the monthly rate you enter, and does not add the separate 0.5% penalty.

DOR’s own statement may differ in method; ask for its computation.

Can Massachusetts interest be waived?

DOR’s information sheet says it will consider waiving interest and penalties and that you can avoid them by paying on time. Ask in writing and offer a payment plan. The penalties are kept by DOR; interest goes to the obligee.

Is a late payment already a judgment in Massachusetts?

Yes. Any installment of support is, on or after the date it is due, a judgment by operation of law with the full force and attributes of a judgment, and an unpaid obligation is a lien in favor of the obligee as of the date due (c. 119A, s. 13(a); s. 6(b)). That is separate from any interest.

Is the interest collected like support?

Any penalty, fee or interest the chapter authorizes the IV-D agency to assess is collected and enforced by the same means as child support (c. 119A, s. 2). Ask whether it is included in income withholding.

Is the interest part of what the child support lien secures?

The lien is for an amount sufficient to satisfy the unpaid child support and incorporates support that accrues in the future (c. 119A, s. 6(b)); ask whether interest is added to the amount shown on a recorded lien before you pay it off.

Who decides whether a penalty applies?

The penalty and the interest are assessed by the IV-D agency under its regulations, and an obligor can dispute an enforcement action through DOR’s review process. Ask for the regulation and the computation in writing (c. 119A, s. 6(a)).

Does the weekly installment matter for the interest?

Yes. Because Massachusetts orders are weekly, each week is its own installment and its own judgment, so interest builds from each due date. The calculator counts weeks from each due date to today.

Where do you get the official figure?

From DOR Child Support Services or the court. See whether arrears expire or can be forgiven and file to modify if your circumstances changed.

Frequently asked questions

Official sources

• G.L. c. 119A, s. 13: judgment by operation of law; retroactive modification
• G.L. c. 119A, s. 6: arrearages; collection; liens; interest and penalties by regulation
• G.L. c. 119A, s. 16: license revocation and suspension
• DOR: Information for parents who pay child support
• G.L. c. 208, s. 36: security and enforcement
• 15 U.S.C. 1673: restriction on garnishment
• 42 U.S.C. 652(k): denial of passports

This is general information, not legal advice. It is based on the cited Massachusetts statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed Massachusetts attorney.