Mass Save in MLP Towns: What You Can and Can't Get

If your electric bill comes from Eversource, National Grid, or Unitil, you can use Mass Save. If it comes from your town's own utility, you cannot use Mass Save for electric measures, but that is not the end of the answer, and almost every competing page stops there and gets it wrong. 50 Massachusetts municipalities are served by one of the state's 41 municipal light plants (MLPs). Whether a home in one of them can still get a Mass Save rebate, and which kind, depends on two more things: who sends the gas bill, and, for a heat pump specifically, what heating system you are replacing. Weatherization like windows and insulation follows a simpler rule than heat pumps do, and both are below. This guide is the decision tree, and as far as we can tell it is the only version online that gets all four outcomes right.

The whole answer in one table

Three questions decide it: who is your electric utility, who is your gas utility, and what are you replacing.

Your situation	Mass Save result
Electric from Eversource, National Grid, or Unitil	Eligible. You pay into Mass Save, you can draw from it.
Electric from an MLP, gas from a Mass Save gas sponsor	Depends. A heat pump replacing that gas heat qualifies through your gas account, though replacing oil, propane, or electric resistance does not. Weatherization, including windows and insulation, qualifies through any participating gas account, even gas that only runs a water heater.
Electric from an MLP, and gas is municipal too	No Mass Save path. Neither bill pays in. Holyoke and Westfield are in this group.
Electric from an MLP, and two gas companies in town	Depends on your gas bill. Middleborough and Wakefield each have municipal gas in part of town and an investor-owned gas company in the rest: a home on Eversource gas (Middleborough) or National Grid gas (Wakefield) has the gas route above, and a home on the town's own gas has none.
Electric from an MLP, and no gas service at all	No Mass Save path. No home has a gas account, so none participates. Ashburnham, Chester, Gosnold, Paxton, Princeton and Templeton are in this group, and so is the light plant side of Russell.

Everything below is the detail behind those five rows.

Why MLP customers can't use Mass Save electric rebates

Mass Save is not a state agency and not a public program in the way most people assume. It is a joint efficiency plan run by the investor-owned utilities (Eversource, National Grid, and Unitil for electric, those three plus Berkshire Gas, Liberty, and Cape Light Compact for the full sponsor list), approved and overseen by the Massachusetts Department of Public Utilities on a three-year cycle.

The money comes from a line item on the electric and gas bills those utilities send, often labeled the energy efficiency reconciliation factor or similar. If your monthly electric bill comes from your town's MLP, you do not pay that surcharge, so you have no claim on the electric side of the pool. That is the whole logic. It is not a snub of MLP customers, it is how the funding rule works. The state publishes the list of municipally-owned electric companies, and per that list 41 MLPs serve all or part of 50 municipalities.

The heat pump rule almost everyone gets wrong

Here is the correction that flips the answer for a lot of families. Mass Save does not classify the whole-home heat pump rebate as an electric-only measure. It classifies it by the fuel you are replacing:

• Replacing a natural gas heating system: eligible if Berkshire Gas, Eversource, Liberty, National Grid, or Unitil is your Mass Save gas sponsor. You apply on your residential gas account.
• Replacing oil, propane, or electric resistance: eligible if Cape Light Compact, Eversource, National Grid, or Unitil is your Mass Save electric sponsor. You apply on your residential electric account.

Read those two rules against an MLP-electric home. If you heat with gas from one of the sponsors above, you are replacing gas, so you apply on the gas account, and the MLP on your electric bill does not disqualify you. If you heat with oil, propane, or electric resistance, the only door is the electric account, and a municipal electric customer does not have a participating electric sponsor. So the honest one-line verdict for an MLP-electric home is "depends on what you heat with," not "not eligible," and not "depends on your gas," which would tell an oil-heated household maybe when the answer is no.

Reading Municipal Light Department states the general principle in its own rebate FAQ: RMLD customers served by a Mass Save participating natural gas provider may be eligible for natural-gas-specific rebates from Mass Save. The rule is statewide, not a Reading quirk. Read the top of your gas bill. If it names Eversource, National Grid, Berkshire Gas, Liberty, or Unitil, do not let a contractor tell you MLP customers "get nothing from Mass Save." That is the flat wrong answer.

Windows, insulation, and weatherization work differently

Weatherization is not a heat pump, and the rule is not the same. You are not replacing a heating system, so there is no "what you heat with" branch. Mass Save weatherization, which includes the ENERGY STAR window rebate, insulation, and air sealing, is open to any customer of a participating utility, electric or gas. For a municipal-electric home the electric side is closed, so it comes down to a single question: do you have a participating gas account?

If your gas comes from Eversource, National Grid, Berkshire Gas, Liberty, or Unitil, that route is open, and the account is enough on its own. It does not matter what the gas actually heats. A home that burns oil for heat but runs a gas water heater on a National Grid account still has a participating gas account, and so still has a window and insulation route. The only municipal-electric homes fully shut out of weatherization are the ones with no participating gas account at all: homes in Holyoke and Westfield, where all the gas is municipal, homes on the town's own gas in Middleborough and Wakefield, and homes in the towns with no gas service at all. So for windows the honest question is not what you heat with, but whether any gas bill in the house comes from a Mass Save sponsor.

The towns with no Mass Save path at all

For most MLP towns, gas comes from an investor-owned sponsor, so the household-level rule above applies. In the towns below, the second bill closes the last door for some or all homes. We checked every light plant town against the state's list of gas companies by city and town in October 2026.

Two towns run their own municipal gas utility alongside their municipal electric, with no other gas company: Holyoke (Holyoke Gas and Electric) and Westfield (Westfield Gas and Electric). In these towns both the electric bill and the gas bill come from the town, so neither pays into Mass Save. There is no gas-account path and no electric-account path.

Two more towns have two gas companies, each serving part of town. In Middleborough, gas comes from Middleborough Gas and Electric or from Eversource; in Wakefield, from Wakefield Municipal Gas and Light or from National Grid. A home with an Eversource gas account in Middleborough, or a National Grid gas account in Wakefield, has the gas route described above. A home on the town's own gas, or with no gas, has no Mass Save path, so read the name on the gas bill. The DPU electric register cannot show you any of this, because it only lists electric companies, which is exactly why "Wakefield Municipal Light Department" on that list hides the word Gas.

Six towns have no natural gas service at all: Ashburnham, Chester, Gosnold (Cuttyhunk Island), Paxton, Princeton and Templeton. None of them appears on the state's gas list, so there is no participating gas account to reach. Russell has no gas service either, so homes on its light plant side have no route. Lakeville is not in this group: Middleborough Gas and Electric supplies its electricity but not its gas, and Eversource serves Lakeville with gas, so the household rule above applies.

One boundary case worth naming: Holyoke Gas and Electric also pipes gas into Southampton and Leverett, but those two towns have investor-owned electric, so they still qualify through the electric account for most measures. If you are in Southampton or Leverett and heat with that municipal gas, the gas-replacement heat pump path is closed to you, but the oil-or-resistance path through your electric utility is open. Confirm with a Mass Save assessment.

Outside Mass Save is not automatically worse

The lazy shorthand is that MLP customers lose out. For a one-shot install that is often true. For a phased project it can be the opposite, and the reason is structural: some MLPs cap their heat pump rebates per calendar year with an annual reset, where Mass Save caps its heat pump rebates per account. If you split electrification across two winters on a rebate with an annual cap, that cap can be claimed twice. That structural point is the durable one. The figures below prove it, and each is dated so you can see when we last checked; confirm the current schedule with the utility before you sign.

• Concord (CMLP): whole-home air source $3,000 per ton up to $10,000 per home; partial-home $1,250 per ton up to $10,000 per home per year; ground source up to $15,000. Rebates are capped per service address per calendar year, $10,000 for air source and $15,000 for ground source, and the cap resets each January, so a project phased over two years on partial-home rebates can collect more than a one-year job. (Checked September 2026.)
• Reading (RMLD): $2,000 per ton up to $8,000 for a new whole-house install, or $400 per ton up to $4,000 for a replacement, with weatherization required and covered at 50% up to $3,500, or a 0% interest heat pump loan instead of the rebate. (Checked September 2026.)
• Wellesley (WMLP): $8,500 if you remove and decommission the existing system, or $6,500 if you keep it, for a whole-home system carrying 90% to 120% of the heating load. Partial-home is $1,125 per ton up to $5,000. (Checked September 2026; the higher 2025 levels were honored only for applications filed by February 28, 2026.)

Against the Mass Save whole-home rebate (see the heat pump rebates guide for current sourced figures), a single-year Concord whole-home project comes out ahead ($10,000 against $8,500), and a project phased over two calendar years on Concord's partial-home rebate can collect more again because its annual cap resets. The other MLPs vary widely, and some pay less than Mass Save. The point is only that "MLP town equals worse rebate" is not automatic. For dollar figures on any other MLP, that utility publishes its own current schedule; amounts and rules change by year, so confirm before signing.

One footnote competitors keep getting wrong: the federal 25C tax credit expired December 31, 2025 under Public Law 119-21 and does not apply to any 2026 or later install. Do not budget around it.

The 50 municipal light plant towns

Each town links to its local HVAC contractor page. The path column is the quick read: electric only means the household rule (depends on your gas and what you heat with) applies, depends on gas company means the town has two gas companies and only the investor-owned one opens a route, no path means both bills are municipal or there is no gas.

Town	Municipal electric utility	Mass Save path
Ashburnham	Ashburnham Municipal Light Plant	no path (no gas)
Belmont	Belmont Municipal Light Department	electric only
Berkley	Taunton Municipal Lighting Plant	electric only
Boxborough	Littleton Electric Light and Water Department	electric only
Boylston	Boylston Municipal Light Department	electric only
Braintree	Braintree Electric Light Department	electric only
Chester	Chester Municipal Electric Light Department	no path (no gas)
Chicopee	Chicopee Municipal Lighting Plant	electric only
Concord	Concord Municipal Light Plant	electric only
Danvers	Danvers Electric Division	electric only
Dighton	Taunton Municipal Lighting Plant	electric only
Georgetown	Georgetown Municipal Light Department	electric only
Gosnold	Gosnold Electric Light Company	no path (no gas)
Groton	Groton Electric Light Department	electric only
Groveland	Groveland Municipal Light Department	electric only
Hingham	Hingham Municipal Light Plant	electric only
Holden	Holden Municipal Light Department	electric only
Holyoke	Holyoke Gas and Electric Department	no path (municipal gas too)
Hudson	Hudson Light and Power Department	electric only
Hull	Hull Municipal Lighting Plant	electric only
Ipswich	Ipswich Municipal Light Department	electric only
Lakeville	Middleborough Gas and Electric Department	electric only
Littleton	Littleton Electric Light and Water Department	electric only
Lynnfield	Reading (RMLD) or Peabody (PMLP), by address	electric only, split
Mansfield	Mansfield Municipal Electric Department	electric only
Marblehead	Marblehead Municipal Light Department	electric only
Merrimac	Merrimac Municipal Light Department	electric only
Middleborough	Middleborough Gas and Electric Department	depends on gas company (Eversource or municipal)
Middleton	Middleton Municipal Light Department	electric only
North Attleborough	North Attleborough Electric Department	electric only
North Reading	Reading Municipal Light Department (RMLD)	electric only
Norwood	Norwood Municipal Light Department	electric only
Paxton	Paxton Municipal Light Department	no path (no gas)
Peabody	Peabody Municipal Light Plant	electric only
Princeton	Princeton Municipal Light Department	no path (no gas)
Raynham	Taunton Municipal Lighting Plant	electric only
Reading	Reading Municipal Light Department (RMLD)	electric only
Rowley	Rowley Municipal Lighting Plant	electric only
Russell	Russell Municipal Lighting Company (north only)	split; no path on the light plant side (no gas)
Shrewsbury	Shrewsbury Electric and Cable Operations	electric only
South Hadley	South Hadley Electric Light Department	electric only
Sterling	Sterling Municipal Light Department	electric only
Stow	Hudson Light and Power Department	electric only
Taunton	Taunton Municipal Lighting Plant	electric only
Templeton	Templeton Municipal Lighting Plant	no path (no gas)
Wakefield	Wakefield Municipal Gas and Light Department	depends on gas company (National Grid or municipal)
Wellesley	Wellesley Municipal Light Plant	electric only
West Boylston	West Boylston Municipal Lighting Plant	electric only
Westfield	Westfield Gas and Electric Light Department	no path (municipal gas too)
Wilmington	Reading Municipal Light Department (RMLD)	electric only

Two split towns you have to check by address

Lynnfield is split between two MLPs. Some addresses are served by Reading Municipal Light Department (RMLD), others by Peabody Municipal Light Plant (PMLP). The boundary follows historical service territory, not the town line, so the electric bill is the only reliable answer.

Russell is only partly on the Russell Municipal Lighting Company. The northern part of town is on the MLP, and the rest is served by an investor-owned utility and is Mass Save eligible. Again, the electric bill decides it.

How to read your own electric bill

The utility that sends your electric bill is your electric utility, full stop. Look at the top:

• Eversource, National Grid, or Unitil means an investor-owned utility, and Mass Save electric rebates apply.
• A town name (Belmont Light, Concord Municipal Light Plant, Reading Municipal Light Department, and so on) means an MLP, and Mass Save electric rebates do not apply. Ask your MLP about its own heat pump and weatherization program, and check your gas bill for the paths above.
• A competitive supplier name (Constellation, Direct Energy, a municipal aggregation brand) is only generation. Look at who runs the delivery, or wires, side. That is your utility for Mass Save purposes.

Municipal aggregation changes the price of generation, not the utility running the wires, and the wires utility is what controls eligibility.

If you are on an investor-owned utility: weatherize first

Skip this if your bill comes from an MLP. On Eversource, National Grid, or Unitil, the sequence for the whole-home heat pump rebate is the part most people get wrong. For a home built before 2000 with no weatherization on file, Mass Save requires sufficient weatherization before it pays the heat pump rebate:

1. Book the no-cost Mass Save Home Energy Assessment first. The assessor documents your insulation and air sealing.
2. Complete the air sealing and insulation it identifies (Mass Save covers most of the cost, see insulation rebates).
3. Then book the heat pump install and submit the whole-home application.

Homes built in 2000 or later, or with an assessment showing under $1,000 of recommended weatherization, skip the prerequisite. Everyone else needs the assessment first, and skipping it is the most common reason a rebate is denied after the install. Equipment financing is available through the Mass Save HEAT Loan.

Frequently asked questions

Am I eligible for Mass Save rebates in an MLP town?

Not for electric-side rebates. But if you heat with gas from a Mass Save gas sponsor (Eversource, National Grid, Berkshire Gas, Liberty, or Unitil), a heat pump replacing that gas heat, and gas-specific rebates, are still available through your gas account. If all your town's gas is municipal (Holyoke, Westfield), you are on the town's own gas in Middleborough or Wakefield, or your town has no gas service (Ashburnham, Chester, Gosnold, Paxton, Princeton, Templeton, and the light plant side of Russell), there is no Mass Save path, and your MLP's own program is the route.

Can I get the Mass Save heat pump rebate if my electric is an MLP?

Only if you are replacing gas heat and your gas utility is a Mass Save sponsor. You apply on the gas account. Replacing oil, propane, or electric resistance requires a participating electric sponsor, which a municipal electric customer does not have, so that path is closed.

Is the federal 25C tax credit available for MLP-town heat pumps?

No. The 25C credit expired December 31, 2025 under Public Law 119-21 and does not apply to any equipment placed in service in 2026 or later. Some competitor pages have not updated this.

How do I find which utility serves my address?

Read the top of your electric bill and your gas bill. For split towns (Lynnfield, Russell) the electric bill is the only reliable answer, because service territory does not follow the town line.

Are MLP rebates always smaller than Mass Save rebates?

Not automatically. Concord pays $3,000 per ton up to $10,000 for a whole-home air source system, and its partial-home rebate resets each calendar year, so a project phased over two years can beat Mass Save's per-account cap on total dollars. Confirm the current schedule with your utility before signing.

Ready to compare heat pump quotes? Get estimates from HVAC contractors serving your town, or browse the full Massachusetts HVAC directory.