National Grid Heat Pump Rate in Massachusetts (2026)

A homeowner in Worcester installs a cold-climate heat pump in October, feeling good about ditching oil. Then the first real freeze hits in January and the electric bill is nearly double what she paid all summer. The heat pump is working exactly as designed. The problem is she is on the wrong rate.

For National Grid customers in Massachusetts, there is a specific electricity rate structure built around heat pump loads. Getting on the right rate, or pairing the right supply price with it, can turn that bill shock into something much more manageable. This post explains how the National Grid heat pump rate works, what the current supply numbers look like, and how to figure out whether staying on Basic Service or switching to a competitive supplier makes more sense for your home.

National Grid files its rate structures with the Massachusetts Department of Public Utilities (DPU), which approves any changes before they take effect. The heat pump rate, sometimes referenced as a time-varying or off-peak heating rate, is a delivery-side program that charges customers a lower per-kWh amount during designated off-peak windows, typically overnight and on weekends, in exchange for enrolling their heat pump load under that tariff.

The mechanics matter. Your bill has two main cost components: delivery (the wires, meters, and infrastructure that National Grid owns) and supply (the actual electricity commodity). The heat pump rate affects the delivery side. Supply is a separate line item, and that is where Basic Service and competitive suppliers come in.

To enroll, you generally need a qualifying electric heat pump as your primary heating source and a meter that can record time-of-use consumption. National Grid handles enrollment; contact them directly or check their website for current eligibility rules, because the DPU can approve program changes at any time.

If you have never chosen a competitive electricity supplier, you are automatically on Basic Service, which is National Grid's default supply rate. Basic Service is set by the utility and approved by the DPU. It changes periodically, usually every six months, based on wholesale market conditions.

As of August 2026, National Grid's Basic Service supply rate is approximately 17.2 cents per kWh. That figure covers only the supply portion of your bill. Delivery charges, the heat pump rate savings, taxes, and other fees layer on top.

For a household running a heat pump through a Massachusetts winter, supply can represent a substantial share of total cost. A heat pump that consumes, say, 800 kWh in a cold month is generating over $130 in supply charges alone at that rate, before delivery. That context is why shopping supply separately, or enrolling in any available heat pump delivery discount, matters more for heating customers than for a household running only lights and appliances.

Yes, sometimes. Massachusetts is a deregulated electricity market, meaning you can choose a third-party supplier for the supply portion of your bill while National Grid continues to deliver the electricity and administer any heat pump rate benefits you are enrolled in. The two decisions, delivery rate enrollment and supply choice, are independent.

As of August 2026, the lowest competitive supplier rate available in Massachusetts is approximately 15.1 cents per kWh, though that figure varies by utility territory and offer terms. Compared to National Grid's Basic Service at roughly 17.2 cents, a customer who qualifies for that rate and uses 8,000 kWh per year could see meaningful annual savings on supply alone. Heat pump customers tend to use more electricity than average, so the gap in dollars is proportionally larger.

The catch: competitive supplier offers come with different contract lengths, fixed versus variable pricing, and early termination terms. A rate that looks attractive in August can look different in February if it is variable. Always read the full contract before enrolling. The state comparison tool, Energy Switch Massachusetts, lists licensed suppliers and current offers side by side so you can compare without calling each company individually.

For a full look at what suppliers are offering right now in the National Grid territory, visit ElectricRates.org's Massachusetts page for live rate data.

National Grid also serves Nantucket under a separate rate structure. As of August 2026, the Nantucket Basic Service supply rate is also approximately 17.2 cents per kWh, in line with the mainland National Grid territory.

Island customers face additional constraints. Transmission infrastructure is limited, competitive supplier options may be fewer, and the DPU has historically taken a closer look at supply offers in constrained territories. If you are a Nantucket homeowner with a heat pump, the delivery-side heat pump rate is still worth exploring, but verify current supplier availability directly through Energy Switch Massachusetts or by contacting National Grid, because the competitive market on Nantucket operates differently than in Worcester or Springfield.

Massachusetts has two major investor-owned utilities. If your service address is in eastern Massachusetts or parts of central and western Massachusetts served by Eversource, you are on a different utility's tariff. Eversource's Basic Service rate as of August 2026 is approximately 17.3 cents per kWh, a fraction of a cent above the National Grid Basic Service rate.

Eversource also has heat pump rate programs filed with the DPU, though the specific tariff names, enrollment processes, and off-peak window definitions differ from National Grid's. If you are unsure which utility serves your address, check your bill's header or look up your address on each utility's website.

The broader point is consistent across both utilities: heat pump owners benefit from actively managing both the delivery rate they are enrolled in and the supply rate they are paying. Letting both default by inertia often means leaving money on the table.

Yes, additional programs exist, though eligibility thresholds and benefit amounts change and this post cannot state current figures with certainty. The main ones to know:

LIHEAP (Low Income Home Energy Assistance Program) provides federally funded heating assistance. Heat pump households running on electricity can qualify. Contact your local Community Action Agency or the Massachusetts Executive Office of Energy and Environmental Affairs to check current income limits and application windows.

National Grid's low-income discount programs, filed with the DPU, offer bill credits or reduced delivery rates for qualifying customers. Enrollment typically happens through the utility directly or through a community assistance organization.

Mass Save, the statewide energy efficiency program administered through the utilities, also offers rebates on heat pump equipment and sometimes incentives tied to time-of-use enrollment. Mass Save is a separate program from supply choice, but the two can stack: get a rebate on the equipment, enroll in the heat pump delivery rate, and shop supply through a competitive offer. That combination is the most complete approach to managing cost.

For the most current income thresholds and program details, go directly to the Mass Save website or call the LIHEAP hotline listed on the Massachusetts Executive Office of Housing and Livable Communities site.

Your National Grid bill lists your rate schedule near the top of the first page, usually a code like R-1 or R-2 or a specific rate name. If you do not see a heat pump or time-of-use designation, you are probably on the standard residential rate and potentially leaving the heat pump discount on the table.

To enroll or to confirm eligibility, contact National Grid's customer service line listed on your bill or log in to your online account. The DPU maintains a docket system at mass.gov/dpu where you can find filed tariffs for both National Grid and Eversource if you want to read the exact rate language.

For supply, visit ElectricRates.org's Massachusetts electricity rates page or go directly to Energy Switch Massachusetts to see what competitive suppliers are currently offering in your zip code. Both tools let you compare without committing.

Three steps, in order.

First, call National Grid or log in online and confirm whether your account is enrolled in the heat pump delivery rate. If you have a qualifying system and you are not enrolled, ask to be enrolled. This affects the delivery side of your bill regardless of who supplies your electricity.

Second, note your current supply rate. If it is 17.2 cents (Basic Service as of August 2026), check Energy Switch Massachusetts or ElectricRates.org to see if a fixed-rate competitive offer is available below that. The lowest available in the state is around 15.1 cents as of August 2026, though offers change frequently and vary by territory.

Third, if you qualify for LIHEAP or a National Grid low-income discount, apply before the heating season starts. Program funds are limited and applications close once funding is exhausted.

Heat pumps are efficient machines, but electricity price matters. A customer who optimizes all three levers, the delivery rate, the supply price, and available assistance programs, will see a materially different winter bill than one who does nothing.