Net Metering in Massachusetts: What Solar Homeowners Need to Know in 2026

If you've been looking into solar in Massachusetts, you've probably noticed that the financial case looks compelling — even without the federal tax credit, which expired at the end of 2025. A big reason for that is net metering. It's one of the most important pieces of the solar savings picture, and Massachusetts has historically offered one of the strongest versions in the country.

Here's a clear breakdown of what net metering is, how it works specifically in Massachusetts, what the current regulatory picture looks like, and what it means for homeowners thinking about going solar right now.

What Is Net Metering?

Net metering is a billing policy between you and your utility. When your solar panels produce more electricity than your home is using at a given moment, that surplus flows back to the grid. Net metering determines what you get in return for it.

Under a full retail-rate net metering program — which Massachusetts currently has — you receive a bill credit for exported electricity at the same rate you'd pay to purchase it. In 2026, that means approximately $0.28/kWh for Eversource customers, $0.32/kWh for National Grid, and $0.28/kWh for Unitil. Those are among the highest credit rates in the country.

Without net metering, utilities would pay a wholesale rate for your excess power — often just 3–5 cents per kWh — while still charging you full retail when you draw from the grid. The difference between those two scenarios has a dramatic effect on whether solar pencils out financially.

How Net Metering Works in Massachusetts

Massachusetts net metering is governed under state law (M.G.L. c. 164, § 139) and administered through DPU regulations (220 CMR 18.00). For residential systems up to 25 kW, here's how the mechanics work:

Monthly credit banking. When your panels overproduce in a given month, you earn credits at the full retail rate. Those credits roll over month to month and apply against future bills — supply charges, delivery charges, and more.

Annual true-up. Credits accumulate throughout the year. At the end of the annual billing cycle — April for Eversource customers, March for National Grid and Unitil customers — any remaining unused credits are reconciled. Leftover balances are paid out at the wholesale avoided-cost rate, which typically runs around 3–5 cents per kWh.

Cap exemption for residential systems. Massachusetts has a statewide net metering cap that limits total participation within each utility territory. However, as of February 2025, residential systems up to 25 kW AC are automatically cap-exempt — meaning they qualify for net metering without needing a cap allocation, regardless of whether the utility's general cap is full. This is an important recent change; the previous cap-exempt threshold was 10 kW.

25-year term lock-in. Once your system is interconnected and enrolled in net metering, your credit structure is locked in for 25 years from the placed-in-service date. Even if Massachusetts changes its net metering rules in the future, your system keeps the terms that were in place when you enrolled.

Which Utilities Offer Net Metering in Massachusetts?

Massachusetts' three investor-owned utilities (IOUs) are all required to offer net metering:

• Eversource — serving eastern and western Massachusetts, including most of Greater Boston and the Pioneer Valley
• National Grid — serving Greater Boston, Worcester, and Cape Cod
• Unitil — serving the Fitchburg area and surrounding communities

These three cover the majority of Massachusetts residents. The remainder are served by Municipal Light Plants (MLPs) — locally owned utilities like the Reading Municipal Light Department or Braintree Electric Light Department — and MLP policies vary. Some MLPs offer net metering programs comparable to the IOUs; others offer lower credit rates or different billing structures. If you're in MLP territory, it's worth calling your utility to understand exactly what's available.

A Second Income Stream: The SMART Program

One thing that sets Massachusetts apart from most states — including Florida — is that net metering isn't the only incentive running in parallel. The Solar Massachusetts Renewable Target (SMART) program pays solar owners a fixed rate per kWh of total generation for 20 years, completely separate from net metering credits.

Under SMART 3.0 (the current version), residential customers earn approximately $0.03/kWh on all power their system produces, regardless of whether it's used on-site or exported to the grid. For a 10 kW system producing around 11,000–12,000 kWh annually, that works out to roughly $330–$360 per year in SMART payments on top of net metering savings.

It's a modest number on its own, but it's predictable — your SMART rate is locked for the full 20-year term — and it stacks directly on top of net metering credits. The two programs operate independently.

One important caveat as of early 2026: the DPU is still reviewing the SMART 3.0 tariff (docket D.P.U. 25-175). Final Statements of Qualification are not currently being issued until that review is complete, so payment start dates may lag behind system installation. Confirm the current program status with your installer before assuming when SMART payments will begin.

The Regulatory Picture Right Now

Massachusetts has maintained some of the most favorable net metering rules in the country for years. But 2026 brings a meaningful shift in the policy environment that every homeowner should understand.

In December 2025, the Massachusetts Department of Public Utilities (DPU) opened a formal investigation — docket D.P.U. 25-200 — examining electric rate design and, specifically, whether to reduce the value of net metering credits. The DPU's own filing noted it would compare Massachusetts rates to other states that "offer lower compensation."

This is an active regulatory proceeding, not a proposal that has been adopted. No changes are in effect yet. But the DPU investigation follows a well-worn path: California reduced its net metering credit by roughly 75% after a similar review; Illinois cut its by about half. The risk of a similar outcome in Massachusetts is real and worth taking seriously.

One specific proposal that has surfaced in the DPU 25-200 context: a tiered structure that would preserve full retail-rate credits for systems up to 10 kW while reducing credits for systems between 10–25 kW to around 60% of retail. Comment periods ran through spring 2026. A final decision could come within 6–12 months after that.

This matters a great deal because of the 25-year lock-in rule. Homeowners who interconnect under the current rules are grandfathered into today's credit structure for the life of their system. Homeowners who wait may find themselves subject to a different — and less favorable — framework.

What This Means If You're Considering Solar

Massachusetts electricity rates are among the highest in the country, which makes the value of net metering credits here unusually significant. Even without the federal tax credit (which expired December 31, 2025 for cash and loan purchases), the combination of high retail rates, full 1:1 net metering, and SMART program income continues to make solar financially compelling for most Massachusetts homeowners.

A typical 10 kW residential system in Massachusetts can generate combined net metering and direct consumption savings in the range of $3,200–$3,800 per year, with another $330–$360 in SMART income on top. That translates to a payback period in the neighborhood of 6–7 years on a system with a 25+ year productive life.

Massachusetts also offers a couple of other incentives worth knowing about:

Sales tax exemption. Solar equipment and installation labor are fully exempt from Massachusetts' 6.25% sales tax under MGL Chapter 64H, Section 6(dd). On a typical residential installation, that's roughly $1,300–$2,000 in upfront savings.

Property tax exemption. Solar adds real value to your home, but Massachusetts exempts that added value from property tax assessment for 20 years. You get the home value benefit without the tax bill to match.

State income tax credit. Massachusetts offers a 15% state income tax credit on solar installations, up to $1,000 — a modest number but worth capturing.

Net Metering and Battery Storage

Battery storage has become an increasingly common conversation for Massachusetts homeowners — and for good reason beyond just net metering.

A solar-plus-battery system still exports excess power to the grid under normal net metering rules when the battery is full. But in practice, pairing a battery means you'll export less, because the battery captures surplus that would otherwise leave your home. For most homeowners, that's actually the better trade — you're using your own electricity at night rather than buying it back from the grid.

Massachusetts also has a program called ConnectedSolutions, run by Eversource and National Grid, which pays battery owners to discharge their stored energy during peak grid demand events. In summer, that can mean 10–30 discharge events; in winter, 5–10. The payments are among the highest battery demand response rates in the country, and they're completely separate from both net metering and SMART income.

One note: Unitil customers are not eligible for ConnectedSolutions. If you're in Unitil territory, a battery still provides real value through SMART battery adders and backup power, but demand response payments won't be part of the picture.

A Note on System Sizing

Like in most states, Massachusetts net metering is designed to work best when your system is sized to cover your actual consumption — not significantly more. At the annual true-up, any remaining credits are paid out at wholesale avoided-cost rates of 3–5 cents per kWh, while you'd be buying replacement power at 28–32 cents per kWh. Deliberately oversizing to accumulate credits isn't a winning strategy on the margins.

A well-designed system aims to offset close to 100% of your annual usage, which is also what your installer will target based on your utility account history.

The Bottom Line

Massachusetts currently offers one of the strongest net metering programs in the country — full retail-rate credits, monthly rollover, a 25-year lock-in, and a cap exemption that now covers systems up to 25 kW. Layered on top of that is the SMART program, generous state incentives, and some of the highest electricity rates in the nation, which amplify the value of every credit you earn.

The open question is how long the current framework holds. The DPU's investigation into net metering credit values is real and active. The pattern in other states suggests that favorable policies do change — and that the homeowners who lock in current terms before a policy shift come out significantly ahead over the long run.

If you're evaluating solar in Massachusetts, this is a moment where the current incentive environment is both genuinely attractive and genuinely in flux. Understanding net metering is the starting point for understanding what solar is actually worth at your address.

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Lunex Power installs solar panel systems and home battery storage across Massachusetts, Florida, Connecticut, Rhode Island, Colorado, North Carolina, and South Carolina. Get a free quote to see what solar looks like for your home.