Massachusetts judgment & prejudgment interest rates
Everything Massachusetts charges in interest on a money judgment or an overdue debt, in one place — the rate after judgment and the rate before it, each verified against the statute and linked to its full page with sources, history, and carve-outs.
| Metric | Rate | Basis |
|---|---|---|
| Post-judgment interest | 12% | Set by statute |
| Prejudgment interest | 12% | Fixed by statute |
Post-judgment interest
Massachusetts's post-judgment interest rate is 12% per year. Massachusetts adds interest at 12% per year to damages in tort actions (M.G.L. c.231 §6B, from commencement of the action) and contract actions (§6C, from breach or demand) — among the highest statutory rates in the U.S. In contract cases an established contract rate displaces the 12% default, and judgments against the commonwealth instead bear interest at a Treasury-linked rate capped at 10%.
→ Full Massachusetts post-judgment page — statute, effective-date history, and source.
Prejudgment interest
Massachusetts's prejudgment interest rate is 12% per year (fixed by statute). Massachusetts prejudgment interest is 12% per year, as simple interest under M.G.L. c. 231, § 6B. Prejudgment interest is mandatory and added automatically by the clerk (not discretionary) once damages are awarded.
→ Full Massachusetts prejudgment page — when it applies, accrual, compounding, and carve-outs.
→ Calculate Massachusetts prejudgment interest
Frequently asked
What is the post-judgment interest rate in Massachusetts?
As of July 8, 2026, the Massachusetts post-judgment interest rate is 12% per year. Interest on Massachusetts tort and contract judgments.
What is the prejudgment interest rate in Massachusetts?
Massachusetts's prejudgment interest rate is 12% per year (fixed by statute). Prejudgment interest is mandatory and added automatically by the clerk (not discretionary) once damages are awarded.
Is Massachusetts judgment interest simple or compound, and when does it start?
See each rate's page for the exact compounding rule, accrual date, and statutory carve-outs — Massachusetts prejudgment interest in particular turns on the type of claim.
Compare every state on the state interest-rate index and the prejudgment interest index, or run the numbers with our interest calculators. Reference data only — not legal advice.