Eversource Massachusetts Electricity Rates: What a kWh Really Costs

Your bill has two halves that are set by different people on different dates. Delivery belongs to Eversource and its regulator. Supply is a market price, and in Massachusetts you can buy it from Eversource, your town or a private company. Put your own kWh in below and it adds up the filed charges for your area.

What one kWh is made of

Delivery is now larger than supply. Of the 36.0¢ an eastern home pays, 18.6¢ is delivery, and only about half of that is the distribution charge most people picture. Transmission adds nearly 5¢, and a run of state programmes follows: energy efficiency, solar, net metering, EV charging.

Only one line differs by area on delivery: Cape Cod and Martha’s Vineyard pay more for energy efficiency. The bigger east–west gap is in supply, where the western price is 15.9¢ against 17.3¢.

Added up by GreenCalculus from Eversource’s rate summaries, read 9 November 2026: Boston, Cambridge, South Shore, Cape Cod and Martha’s Vineyard, Western Massachusetts.

Delivery charges normally change on 1 January and 1 July, and the fixed supply price on 1 February and 1 August. So a bill can move four times a year with no change in how much you use. The current summaries took effect on 1 September 2026, outside that usual pattern, which is why it is worth checking the date on any figure you read.

Fixed or monthly price

Every home starts on a fixed Basic Service price for six months. There is a second option that follows the actual cost of power each month. In eastern Massachusetts it runs from 12.5¢ in May 2026 to 25.5¢ in January 2027, twice as much.

Eversource supply price pages: east, west. Eversource says final prices await regulatory approval.

Taken month by month, the variable price averaged 15.3¢ from February to July, against 15.6¢ fixed, and 16.9¢ from August to January, against 17.3¢. That looks like a small win. It is a plain average, though, and many homes use the most power in exactly the months when the variable price is highest. A home that heats with electricity could pay 25.5¢ for power in its heaviest month. Eversource says you can make this switch only once, so read its terms first.

Heat pump and electric-heat rates

The most valuable line in the filing is easy to miss. Rate R-1HP, for homes with an eligible heat pump, cuts winter delivery to 10.8¢. From November to April that is 7.8¢ less per kWh than the standard rate, and it comes mostly from lower distribution and transmission charges. In summer the two rates are almost the same.

Homes on means-tested benefits or fuel assistance can get rate R-2 (or R-4 with electric heat), which takes 42% off the total bill. The calculator above applies it. Ask Eversource to confirm which rate you are on; it is printed on the bill.

Who sells you the power

Most Eversource homes in Massachusetts no longer buy their power from Eversource. By 2025 only 306,795 homes still bought it there; the other 76% had moved to a town aggregation programme or a private contract. Eversource still delivers that power and charges for it, so the delivery figures above apply to everyone.

The two kinds of alternative have very different records. A town programme is approved by the Department of Public Utilities and covers residents who do not opt out. Our Massachusetts page compares what those programmes charge. Private contracts are the risky ones: in March 2026 the Attorney General’s office reported that households on them paid more than $738 million above Basic Service over a decade. Before signing, enter the offer in the calculator’s supply box and compare it with the blank figure.

Why the federal average is wrong here

If you have seen Eversource Massachusetts listed at around 20¢, this is why. The US Energy Information Administration publishes the utility’s average as 19.7¢ for the 12 months to August 2026. No home can be paying that. Basic Service alone is 17.3¢ in the east, leaving under 3¢ for delivery that is filed at 18.6¢.

The fault appears in the 2025 returns. The bars below take the price reported for homes on Basic Service and subtract the price for homes on delivery only, which should leave about the cost of supply. It left 13.6¢ in 2024 and 1.4¢ in 2025.

The 2025 figure also sits almost level with what delivery alone costs: 20.06¢ on EIA’s delivery-only line, close to the filed 18.6¢ once the monthly charge is spread over the kWh. Our reading is that the utility’s reported revenue for Basic Service homes stopped including the supply part. That is an inference, and nothing EIA publishes explains it. We have not changed EIA’s numbers. They remain in the download below, but this page’s charts stop at December 2024 and we leave Eversource Massachusetts out of our rankings until the returns make sense again.

Prices back to 1990

Through December 2024 the federal series holds up. It starts at 10.6¢ in 1990 and reaches 29.9¢ in 2024, up 182.2% over the period; prices in general are up 153.1%. The jump came late: 24.25¢ in 2021, 29.31¢ in 2022. The series joins several older companies, set out further down.

A year of bills

In the last clean years the average bill peaked in January, at $166, and bottomed in October at $108. These figures come before the error above, and prices have moved since, so treat them as the shape of a year, not as today’s bill.

Average for each calendar month over the 36 months to December 2024: bill per home, with the price per kWh that month beneath it.

One company, five old territories

Eversource in Massachusetts is the sum of several older utilities, which is why it still publishes five separate rate summaries. It also explains the steps in any long history of the company.

1. To 2006Boston Edison, Commonwealth Electric and Cambridge Electric report to EIA separately, under the NSTAR group.
2. 2007The three appear in EIA’s returns as one company, NSTAR Electric.
3. 2012NSTAR becomes part of Northeast Utilities, which also owns Western Massachusetts Electric.
4. 2015Northeast Utilities and its companies take the name Eversource.
5. 31 Dec 2017Western Massachusetts Electric merges into NSTAR Electric. EIA’s 2018 customer count jumps to match.
6. TodayOne company on the books, NSTAR Electric d/b/a Eversource, with five rate summaries and two supply areas.

Where it serves

Check your bill if you are unsure. Many Massachusetts towns have their own municipal light plant and are not Eversource customers at all, and National Grid serves much of the rest of the state.

EIA-861 Service Territory, 2025. A county on the list may be served only in part, and other utilities may serve the same county.

Outages

A typical Eversource customer here spent 113 minutes in the dark during 2025. Nationally the figure was 269 minutes. The high point in the federal record, which opens in 2013, is 970 minutes in 2018.

Rooftop solar

Net metering covered 89,475 Eversource homes in Massachusetts as 2025 closed, or 7.0% of its households. Two lines in the table at the top, the distributed solar charge and net metering recovery, are on every R-1 customer’s bill.

EIA-861 Net Metering: homes with solar panels on a net-metering arrangement at the end of each year.

Carbon on your bill

A 600 kWh month of New England grid power comes with about 148 kg of CO₂e, at the regional average published by the EPA. Your own supplier’s mix can differ, and a green tariff changes what is claimed for your power without changing what the grid burned. The calculator at the top works this out for your kWh.

Against National Grid

National Grid is the other big utility in the state. EIA’s figure for its homes on Basic Service is 33.9¢, and the Massachusetts average is 30.4¢, both over the latest 12 months. Those are average prices with the fixed charge folded in, so they are not exact matches for the rate above, but they sit where Eversource’s filed figures say they should. See the 40 biggest utilities for the rest of the country.

How we worked this out

Today’s prices are not estimates. We read each Eversource rate summary and supply page and added up the lines for rate R-1, then checked the delivery total against the 18.635¢ in Eversource’s tariff. The figures are the rate for one more kWh: the monthly charge is shown separately and included in any bill. Taxes do not appear on these summaries. The history comes from EIA-861M and EIA-861 and is revenue divided by kWh, stopped where it stops matching the filings. Municipal programmes and private contracts are not in these prices.

Frequently asked questions

Download the data

The downloads carry EIA’s figures as published, including the months this page leaves out.

• Eversource Massachusetts, every month (CSV)
• All 40 utilities, latest figures (CSV)
• Citable archive on Zenodo (DOI 10.5281/zenodo.24071582): all 40 utilities, with field descriptions
• Dataset, code and history on GitHub

How to cite this page

@dataset{say2026eversourcemassach,
  author    = {Say, Jeremiah},
  title     = {Eversource Massachusetts electricity rates: filed prices and residential price history},
  year      = {2026},
  publisher = {GreenCalculus},
  doi       = {10.5281/zenodo.24071582},
  url       = {https://doi.org/10.5281/zenodo.24071582}
}

Version history

• 1.0 (9 November 2026): launched on the rates Eversource filed from September 2026.