An Act relative to prejudgment interest rates

194th Legislature (2025-2026) Introduced by Jason Lewis

Mass. shifts prejudgment interest from a fixed 12% to a market-based rate tied to a weekly average 1-year Treasury yield, affecting settlements and damages.

Hearing rescheduled to 11/04/2025 from 01:00 PM-05:00 PM in A-1 and Virtual Hearing updated to New End Time

Summary — S.1149: “An Act relative to prejudgment interest rates” (Massachusetts)

Note on source materials: The packet you provided includes multiple unrelated bills that share the number S.1149 (one from Massachusetts concerning prejudgment interest, and a separate Idaho bill concerning foreign ownership of land). The summary below focuses on the Massachusetts bill titled “An Act relative to prejudgment interest rates” (Senate Docket No. 537). A brief summary of the unrelated Idaho S.B. 1149 appears at the end for completeness.

Key provisions

Amends Sections 6B and 6C of Chapter 231 of the Massachusetts General Laws.

Removes the existing flat prejudgment interest rate of “12% per annum.”

Replaces it with a rate “calculated at a weekly average 1‑year constant maturity Treasury yield, as published by the Board of Governors of the Federal Reserve System, for the calendar week preceding the date of the judgment.”

Applies this new calculation wherever the prior statutory 12% prejudgment interest rate was specified in the cited sections.

Who is affected

Plaintiffs and defendants in Massachusetts civil actions in which prejudgment interest is awarded under G.L. c.231, §§6B and 6C.

Lawyers, insurers, and courts will need to compute prejudgment interest using the specified Treasury yield average rather than the previous fixed rate.

Potential impact on settlement negotiations, case valuation, and collection amounts for damages awarded prior to judgment.

Practical impact

Interest becomes variable and tied to market conditions: when 1‑year Treasury yields are low, prejudgment interest will fall below the prior 12% level; when yields rise, prejudgment interest could exceed 12%.

Tends to align prejudgment interest with a widely available, benchmark short‑term risk‑free rate, reducing reliance on an arbitrary statutory rate.

May change plaintiffs’ incentives to litigate versus settle and affect defendants’ exposure (both up or down depending on interest-rate environment).

Procedural / timeline status (from provided materials)

Filed in the Massachusetts Senate: January 13, 2025 (Senate Docket No. 537).

Referred to the Judiciary Committee.

Primary sponsor: Senator Jason M. Lewis.

Materials indicate this bill replaces similar prior matter (Senate No. 1029 of 2023–2024).

Appendix — Brief note on unrelated Idaho S.B. 1149 (also in your packet)
- Substantively different: amends Idaho Code §55‑103 to bar, as of July 1, 2025, foreign governments or foreign state‑controlled enterprises from acquiring or holding a controlling interest in agricultural land, forest land, water rights, mining claims, or mineral rights; authorizes the Idaho Attorney General to seek court‑ordered receiverships to divest prohibited holdings and requires certain procedures for receivership sales and disposition of proceeds. This is a separate state bill and not related to the Massachusetts prejudgment interest proposal.

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