Massachusetts Workers Compensation Guide

Workers Compensation Requirements in Massachusetts

Massachusetts requires workers' compensation for all employers with one or more employees, including household workers who work 16+ hours per week. Massachusetts has a Department of Industrial Accidents (DIA) that oversees the system. Massachusetts workers' comp costs are above-average due to high medical costs and relatively generous benefits.

Workers Comp Rates in Massachusetts

The average rate of approximately $2.05 per $100 of payroll is a statewide blended average — actual rates vary significantly by job classification.

For example, an employer with $1 million in payroll at the average rate of $2.05 per $100 would pay approximately $20,500 annually before experience modification adjustments.

Average Workers Comp Rates by City in Massachusetts

What Makes Massachusetts Unique

Massachusetts requires workers' comp even for household employers who hire domestic workers 16 or more hours per week — a requirement that catches many homeowners off guard. Massachusetts also has a strong attorney involvement culture in disputed claims, and the DIA judge system creates significant hearing activity.

How Massachusetts Rates Are Set — and the 2026 Court Ruling

Massachusetts is not an NCCI state. Rates are filed by the Workers’ Compensation Rating and Inspection Bureau of Massachusetts (WCRIBMA), the state’s sole licensed rating organization, and the Commissioner of Insurance decides whether to approve them after a hearing. The approved manual rates apply to both the voluntary market and the assigned risk pool.

The current rate level comes from an unusual dispute. The Bureau proposed a 7.6% average decrease in December 2023; the Commissioner instead ordered a 14.6% decrease. On July 13, 2026, the Supreme Judicial Court upheld the Commissioner’s authority to reject the Bureau’s filing but held that he had not adequately explained how he arrived at 14.6%, and sent the decision back for a reasoned explanation. Rates reflecting the 14.6% cut remain in place while that remand proceeds.

For employers, the practical point is that Massachusetts rates carry more regulatory uncertainty than usual right now. Budget for renewals with some cushion, and ask your agent at each renewal whether the manual rates have changed since the last policy.

The Massachusetts “Mod”: Experience Rating vs. Merit Rating

When Massachusetts employers ask about their workers’ comp “multiplier,” they usually mean one of two different adjustments, and which one applies depends on premium size:

Thresholds from the WCRIBMA Experience Rating Plan FAQ.

So most very small Massachusetts employers are not on an experience mod at all; they are on merit rating, and a single claim can move them from a credit to a debit. Once premium crosses the experience rating threshold, the mod (1.00 = average) takes over. Either way, the modifier is multiplied against manual premium — see our EMR calculator for how an experience mod is built.

Who Must Be Covered — and Who May Opt Out

• Every employer with one or more employees, regardless of hours worked — part-time workers included.
• Domestic workers must be covered once they work 16 or more hours a week for the household.
• Corporate officers owning at least 25% of the corporation may exempt themselves by filing Form 153.
• Sole proprietors, partners, and LLC members are not required to cover themselves but may opt in.

An exemption covers only the owner. A two-person LLC whose members both work in the business needs no policy; the same LLC with one part-time employee needs one.

Stop-Work Orders: $100 a Day, $250 if You Appeal

The Department of Industrial Accidents’ Office of Investigations enforces coverage directly. An employer found without insurance receives a stop-work order effective immediately, with a fine of $100 per day from the date of issuance. If the employer appeals, the fine rises to $250 per day. Criminal penalties can include up to one year of imprisonment and a fine of up to $1,500.

Two smaller obligations generate fines too: failing to post the required notice showing your insurer can cost $100, and late filing of the first report of injury is $100 per violation. Uninsured employees can still be paid from the Workers’ Compensation Trust Fund, which then pursues the employer for the money.

Reporting Injuries: Form 101 and the Five-Day Rule

Massachusetts benefits start after five calendar days of disability, and the employer’s reporting duty is tied to the same trigger. Once an employee has been disabled for five full or partial days, the employer must file Form 101 (Employer’s First Report of Injury) electronically within seven calendar days, not counting Sundays and legal holidays. Report every lost-time injury to your insurer immediately; the five-day count is the deadline for the state, not a reason to wait.

The Assigned Risk Pool

Employers that can’t find voluntary coverage are placed through the Massachusetts assigned risk pool, administered through WCRIBMA. Assigned risk policies use the same approved manual rates as the voluntary market, but premium discount is not available to them — one reason larger employers work to stay in the voluntary market. Coverage can begin as early as 12:01 a.m. the day after the application and premium are received, which matters if you’re trying to clear a stop-work order.

Workers Comp Benefits in Massachusetts

Massachusetts provides temporary total disability at 60% of average weekly wage. Medical benefits cover necessary treatment through a fee schedule. Permanent partial disability uses a different calculation than most states.

Employee Rights in Massachusetts

Massachusetts workers may choose their own physician. The DIA provides conciliation conferences, conference hearings, and formal hearings for dispute resolution.

How to Reduce Workers Comp Costs in Massachusetts

Massachusetts household employers should check workers' comp requirements for domestic employees. Boston-area high wage environment means temporary disability claims accumulate costs quickly — return-to-work is critical. Safety investments in construction and manufacturing produce strong premium returns in Massachusetts's above-average rate environment.

Frequently Asked Questions

Is workers' comp insurance required in Massachusetts?

Yes. Massachusetts requires workers' compensation coverage for employers with 1 or more employees (including household workers at 16+ hours/week).

How much does workers' comp cost in Massachusetts?

The statewide blended average in Massachusetts is approximately $2.05 per $100 of payroll, though actual rates vary significantly by job classification and claims history — high-risk classifications like construction and roofing pay substantially more than clerical or retail classifications.

Who regulates workers' comp in Massachusetts?

the Massachusetts Department of Industrial Accidents (DIA) oversees Massachusetts's workers' compensation system, handling claims administration, compliance, and dispute resolution between employees, employers, and insurers.

What happens if a Massachusetts employer doesn't carry required workers' comp coverage?

Operating without required coverage exposes a Massachusetts employer to civil penalties, potential personal liability for injury costs, and loss of the exclusive remedy protection that normally shields compliant employers from direct lawsuits over workplace injuries.

Who sets workers’ comp rates in Massachusetts?

The Workers’ Compensation Rating and Inspection Bureau of Massachusetts (WCRIBMA) files rates, and the Commissioner of Insurance approves or disapproves them after a hearing. Massachusetts does not use NCCI. The same manual rates apply in the voluntary market and the assigned risk pool.

What happened with the Massachusetts workers’ comp rate decision in 2026?

The Commissioner had ordered a 14.6% average rate decrease instead of the Bureau’s proposed 7.6% decrease. On July 13, 2026, the Supreme Judicial Court upheld the Commissioner’s authority to reject the Bureau’s filing but required a reasoned explanation for the 14.6% figure and remanded the case. Rates reflecting the 14.6% cut remain in place during the remand.

What is the Massachusetts workers’ comp mod or multiplier?

Employers with premium of at least $11,000 over the last two years of the experience period (or an average of $5,500 a year over longer periods) receive an experience modification factor. Smaller employers with average premium of $500 or more get a credit or debit under the Merit Rating Plan instead, which needs three years of history.

Do corporate officers need workers’ comp in Massachusetts?

Corporate officers who own at least 25% of the corporation may exempt themselves by filing Form 153. Sole proprietors, partners, and LLC members are not required to cover themselves but may choose to. All other employees must be covered.

What is the penalty for no workers’ comp in Massachusetts?

The Department of Industrial Accidents issues a stop-work order effective immediately, with a fine of $100 per day from issuance, rising to $250 per day if the employer appeals. Criminal penalties can include up to a year in prison and a fine of up to $1,500.

When must a Massachusetts employer file a first report of injury?

Form 101 must be filed electronically within seven calendar days, not counting Sundays and legal holidays, after the employee’s fifth full or partial day of disability. Late filing is fined $100 per violation.

The information on this page is provided for general informational purposes only and reflects estimated industry averages and state requirements as of 2026. Workers compensation laws, rates, and requirements change frequently and vary significantly by employer size, industry, and job classification. Rate estimates shown are blended averages and do not represent actual quotes for any specific employer. Always consult a licensed workers' compensation insurance professional and your state's workers' compensation regulatory agency for current, employer-specific information.