How Massachusetts calculates alimony
Massachusetts stands apart from most of the country because its alimony law actually contains math. The 2011 Alimony Reform Act, codified at M.G.L. c. 208, §§48-55 and effective March 1, 2012, replaced the state's older, less structured approach with something closer to a formula. Section 53(b) states plainly that alimony "should generally not exceed the recipient's need or 30 to 35 per cent of the difference between the parties' gross incomes established at the time of the order being issued," except for reimbursement alimony or circumstances warranting deviation. That 30-35% figure is not a practitioner rule of thumb passed around by attorneys; it is written directly into the statute, which sets Massachusetts apart from factor-only states like California or Tennessee.
Duration is just as codified. General Term alimony, the default, ongoing type, runs on a scale tied to how long the marriage lasted. For marriages of five years or less, the maximum term is 50% of the marriage's length in months. That climbs to 60% for marriages between five and ten years, 70% for ten to fifteen years, and 80% for fifteen to twenty years. Past twenty years, the court has discretion to order alimony for an indefinite term with no durational cap at all. On top of the duration table, the 2011 reform built in two automatic off-ramps: alimony generally terminates when the paying spouse reaches full Social Security retirement age, and it can end early if the recipient remarries or cohabits continuously with a new partner for three months or longer.
The formula hasn't stood entirely still in practice, even though the statute itself hasn't been amended. Two lines of case law reshaped how it gets applied heading into 2026. The Supreme Judicial Court's decision in Cavanagh v. Cavanagh, 490 Mass. 398 (2022), requires judges to run the numbers two ways, once treating alimony as the first calculation and once treating child support as the first calculation, then compare the results before issuing an order. Because stacking both obligations can legitimately exceed what an informal 50%-of-income ceiling used to assume, 2025 Appeals Court decisions applying that framework have allowed combined awards reaching 55-60% of gross income in some higher-income cases. Separately, Openshaw v. Openshaw (2025) expanded what counts as "marital lifestyle" under §53 to include a family's historical savings rate, not just its spending. A spouse accustomed to socking away 15-20% of household income during the marriage can now point to that savings capacity as part of their demonstrated need, not just their historical spending pattern.
Fault plays no role here, and that's by design. Before you assume an affair might move the number, know that the enumerated §53 factors (marriage length, age, health, income and employability, economic and non-economic contributions, marital lifestyle, ability to maintain that lifestyle, lost economic opportunity, and a catch-all for other relevant factors) deliberately exclude marital misconduct. The 2011 reform stripped conduct out on purpose, tying Massachusetts alimony to income, need, and marriage length instead. No case law found in this research treats the catch-all clause as a backdoor for fault.
There's also no minimum marriage-length threshold that has to be cleared just to be eligible for General Term alimony in the first place. Unlike states that impose a flat years-married floor before support can even be requested, Massachusetts lets marriage length do its work through the §49 duration table rather than through an eligibility gate. A one-year marriage and a thirty-year marriage are both eligible to seek alimony under §53; what differs sharply between them is how long any award can run and, given the codified 30-35% ceiling, how the income-difference math plays out once a judge applies the other §53 factors.
Last reviewed: July 2026. Statute citations: M.G.L. c. 208, §53 (amount, factors); §49 (General Term duration table); §§48-55 generally (Alimony Reform Act of 2011).
Frequently Asked Questions
Does Massachusetts have an alimony formula?
Yes — Massachusetts is unusual in that this is codified, not just a practitioner guideline. M.G.L. c. 208, §53(b) states that alimony generally should not exceed the recipient's need or 30 to 35 percent of the difference between the parties' gross incomes at the time of the order, whichever is less.
How long does General Term alimony last in Massachusetts?
It's set by a codified duration table tied to marriage length: 50% of the marriage's length in months for marriages of 5 years or less, 60% for 5-10 years, 70% for 10-15 years, 80% for 15-20 years, and an indefinite term at the court's discretion for marriages over 20 years.
Does adultery affect alimony in Massachusetts?
No. The 2011 Alimony Reform Act deliberately removed marital fault from the alimony factors listed in M.G.L. c. 208, §53. Marital misconduct, including adultery, is not one of the enumerated factors and is not a live consideration under current law.
What did Cavanagh v. Cavanagh change about Massachusetts alimony?
The Massachusetts SJC's Cavanagh v. Cavanagh decision (490 Mass. 398, 2022) requires judges to calculate support using both an alimony-first method and a child-support-first method, then compare the two. Because combining both obligations can exceed the old informal 50%-of-income ceiling, 2025 Appeals Court decisions applying Cavanagh have allowed combined awards reaching 55-60% of gross income in some high-income cases.
When does alimony end in Massachusetts?
General Term alimony generally terminates when the payor reaches full Social Security retirement age, and it can terminate early if the recipient remarries or continuously cohabits with a new partner for three months or more. Marriages over 20 years can receive an indefinite term at the court's discretion.