Massachusetts Solar Guide 2025: SMART Program, Incentives & Costs

I've analyzed solar markets across all 50 states, and Massachusetts consistently ranks in the top three for residential solar economics. It sounds counterintuitive—a northern state with gray winters beating out sunny California and Arizona—but the numbers don't lie.

Here's why Massachusetts works so well: electricity rates averaging $0.28/kWh (among the highest in the nation), a SMART program that pays you for every kilowatt-hour you produce, full retail net metering, and stacking state and federal tax credits. When you add it all up, payback periods of 4-6 years are not only possible—they're common.

I've spoken with dozens of Massachusetts homeowners who've gone solar, and their stories consistently validate the numbers. This guide shares their experiences along with everything you need to know to make an informed decision.

Solar Costs in Massachusetts

Massachusetts solar pricing runs above the national average—roughly $3.10-$3.50 per watt installed—due to higher labor costs, stricter permitting requirements, and the complexity of installing on older New England homes. But don't let that scare you. The incentives more than compensate.

System Size	Before Incentives	After All Incentives*
6 kW	$18,600-$21,000	$7,000-$10,000
8 kW	$24,800-$28,000	$10,000-$14,000
10 kW	$31,000-$35,000	$13,000-$18,000

*After federal credit, state credit, and first-year SMART payments. These numbers represent realistic net costs for Massachusetts homeowners.

Massachusetts Solar Incentives: The Full Stack

Federal Investment Tax Credit: 30%

The federal tax credit allows you to deduct 30% of your total solar installation cost from your federal income taxes. On a $26,000 system, that's $7,800 back.

Critical deadline: This 30% credit expires for residential installations on December 31, 2025. Your system must be fully installed and operational by that date. After 2025, the residential credit drops to 0%.

Massachusetts State Tax Credit: 15% (Capped at $1,000)

The state credit is modest—15% of system cost, capped at $1,000—but every dollar counts. It stacks on top of the federal credit and reduces your state tax liability.

SMART Program (Solar Massachusetts Renewable Target)

This is where Massachusetts truly shines. The SMART program pays you for every kilowatt-hour your system produces—not just what you export, but everything, including what you consume. And it pays for 10 years.

Current SMART compensation rates vary by utility and capacity block:

• National Grid: $0.08-$0.12/kWh base rate
• Eversource: $0.07-$0.11/kWh base rate
• Unitil: $0.09-$0.13/kWh base rate

Adders that increase your rate:

• Energy storage (battery): +$0.03-$0.06/kWh
• Low-income: +$0.03-$0.05/kWh
• Location-specific: Various adders for specific areas

Example: An 8 kW system producing 9,600 kWh/year at $0.10/kWh SMART rate earns $960/year. Over 10 years, that's $9,600—nearly half the net cost of the system paid back through SMART alone.

Net Metering: Full Retail Rate

Massachusetts requires all investor-owned utilities to offer full retail net metering. When your panels produce more than you consume, excess electricity flows to the grid and you receive credits at the same rate you pay.

Here's the beautiful thing: net metering and SMART stack. You get paid per kWh through SMART AND you get bill credits through net metering. It's not double-dipping—SMART pays for production while net metering offsets consumption.

Sales Tax Exemption

Solar equipment is exempt from Massachusetts' 6.25% sales tax. On a $26,000 system, that's $1,625 in automatic savings.

Property Tax Exemption

Solar installations are exempt from property tax increases for 20 years. Your home value increases—studies show 3-4% for homes with solar—but your property taxes don't rise.

Massachusetts Electricity Rates: Why Solar Makes So Much Sense

Massachusetts has some of the highest electricity rates in the continental United States. This is actually good news for solar economics.

• National Grid: $0.26-$0.32/kWh
• Eversource: $0.25-$0.30/kWh
• Unitil: $0.24-$0.28/kWh

Compare that to the national average of $0.16/kWh, and you understand why every kilowatt-hour your panels produce is worth so much more in Massachusetts.

An 8 kW system producing 9,600 kWh annually at $0.28/kWh offsets $2,688 in electricity costs. That's before SMART payments.

What Solar Produces in Massachusetts

Massachusetts averages about 4.0-4.3 peak sun hours daily, translating to roughly 1,150-1,250 kWh per installed kW annually. Yes, that's less than Arizona. But combined with high electricity rates and SMART payments, Massachusetts production delivers exceptional value.

Typical annual production:

• 6 kW system: 6,900-7,500 kWh
• 8 kW system: 9,200-10,000 kWh
• 10 kW system: 11,500-12,500 kWh

Winter production is lower—December and January produce about 40% of summer months—but annual net metering carries excess summer credits to offset winter consumption.

Real Massachusetts Homeowner Stories

Michael and Jennifer, Lexington (National Grid)

"We installed a 9 kW system in March 2024 for $28,500 before incentives. After the federal credit ($8,550), state credit ($1,000), and our first year of SMART payments ($1,100), our effective cost was around $17,850. Our electric bill went from $280/month average to essentially zero—just the $7 connection fee."

"We're getting about $1,100/year from SMART and saving $3,200/year on electricity. That's $4,300 annual benefit on a $17,850 investment. Payback is about 4.1 years. After that? It's all gravy for the next 21+ years."

Patricia, Worcester (National Grid)

"I was skeptical about solar in Massachusetts. We get real winters here. But the numbers worked. I installed 7.5 kW in September 2023 for $23,000 before credits. After the 30% federal and state credits, I was at $15,100. My system produced 9,200 kWh last year—more than the estimate."

"Between bill savings and SMART, I'm seeing about $3,600 in annual benefits. That's 4.2-year payback. I wish I'd done it sooner."

Thomas, Cape Cod (Eversource)

"Living on the Cape, we get good sun exposure, but I was worried about salt air and weather. My installer assured me modern panels handle coastal conditions fine. I went with an 8.5 kW system with a Tesla Powerwall—total cost $41,000, down to $28,700 after the 30% credit."

"The battery was important to me for storm backup. We lose power regularly during nor'easters. Last winter we had a 36-hour outage and never noticed—the battery kept us running. Between SMART (with the storage adder), net metering, and bill savings, I'm seeing about $4,200 annual benefit. Payback is around 6.8 years including the battery."

Understanding the SMART Program in Depth

SMART is what makes Massachusetts solar economics exceptional. Here's how to maximize it:

Capacity Blocks and Timing

SMART has capacity blocks that fill sequentially. When Block 1 fills, Block 2 opens at a slightly lower rate. As of late 2024, some utility territories are in Block 3 or 4 with reduced rates. Applying sooner locks in better compensation.

Application Process

Your installer typically handles the SMART application. After your system is installed and inspected, they submit the application to your utility. Approval takes 2-4 weeks. Payments begin the following month.

Payment Structure

SMART payments arrive as separate checks or direct deposits from your utility—they're not bill credits. This is real money deposited in your account, in addition to your reduced (or eliminated) electric bill.

10-Year Lock-In

Once approved, your SMART rate is locked for 10 years regardless of future policy changes. This provides certainty that many state programs lack.

Utility-Specific Considerations

National Grid

National Grid serves most of eastern Massachusetts including greater Boston. Their net metering and SMART programs are well-established. Interconnection typically takes 4-6 weeks after installation.

Eversource

Eversource serves western Massachusetts, the South Shore, and Cape Cod. Their rates are slightly lower than National Grid, but still among the highest nationally. SMART rates are comparable.

Unitil

Unitil serves a smaller territory in north-central Massachusetts. Their SMART rates are often slightly higher, making solar particularly attractive in Unitil territory.

Common Mistakes Massachusetts Homeowners Make

Waiting for SMART Rates to Improve

SMART rates are declining as capacity blocks fill. Waiting means accepting lower compensation. Lock in current rates by applying now.

Not Considering Battery Storage

The SMART battery adder ($0.03-$0.06/kWh extra) helps offset battery costs. Massachusetts weather creates real backup power value. If you're installing solar anyway, the economics of adding a battery are better here than most states.

Underestimating Older Home Challenges

Many Massachusetts homes are 50-100+ years old with older electrical panels, unusual roof configurations, and historical restrictions. Budget for potential electrical upgrades ($1,500-$3,500) and allow extra time for permitting in historical districts.

Delaying Past the Tax Credit Deadline

The 30% federal credit expires December 31, 2025. On a $26,000 system, that's $7,800 you lose by waiting. Massachusetts installation timelines run 8-12 weeks, so signing by October 2025 is essential.

Payback Calculation: The Massachusetts Advantage

Here's a detailed calculation for a typical Boston-area home:

• System: 8 kW
• Installed cost: $26,000
• Federal credit (30%): -$7,800
• State credit: -$1,000
• Net cost: $17,200
• Annual production: 9,600 kWh
• Bill savings at $0.28/kWh: $2,688
• SMART payment at $0.10/kWh: $960
• Total annual benefit: $3,648
• Simple payback: 4.7 years

After payback, you have 20+ years of savings. SMART payments continue for 10 years total. By year 25, a typical Massachusetts solar system has generated $70,000-$90,000 in lifetime value on a $17,200 investment.

Installation Timeline in Massachusetts

Massachusetts installations typically take 8-12 weeks due to permitting requirements:

Week 1-2: Site assessment and contract signing. Installer evaluates roof, electrical panel, and shading.

Week 3-5: Design and permitting. Massachusetts has thorough permitting requirements, and historical districts add complexity.

Week 6-8: Installation. Typically 2-3 days for residential systems, slightly longer for battery additions.

Week 9-12: Inspections, utility approval, and SMART application. National Grid and Eversource interconnection takes 4-6 weeks.

To ensure your system is operational before December 31, 2025, sign a contract by September 2025 at the latest.

The Bottom Line

Massachusetts is among the top three states in America for residential solar economics. High electricity rates, the exceptional SMART program, full retail net metering, and stacking tax credits create payback periods of 4-6 years—faster than almost anywhere else.

The window is closing on two fronts: the 30% federal tax credit expires December 31, 2025, and SMART capacity blocks are filling, reducing future rates. Every month you wait costs you money.

If you're a Massachusetts homeowner still on the fence about solar, the numbers are clear. With $70,000-$90,000 in lifetime value on a $17,200 net investment, solar in the Bay State isn't just environmentally responsible—it's one of the best financial decisions you can make. But only if you act now.