Somerville: heat pumps and Mass Save
55% of Somerville homes are in two-to-four-unit buildings and 70% heat with natural gas. Only 6% use oil, so most projects replace gas, where Mass Save's gas-sponsor rule applies.
- Facts checked: November 3, 2026
How Somerville homes heat today
| Main heating fuel | Homes | Share |
|---|---|---|
| Natural gas | 24,824 | 70% |
| Electricity | 6,905 | 19% |
| Fuel oil or kerosene | 2,202 | 6% |
| Propane or bottled gas | 1,108 | 3% |
| Other or none | 676 | 2% |
35,715 occupied homes: 12,232 owned and 23,483 rented. Median year built: 1938. Of 37,756 housing units, 20,843 (55%) are in buildings of two to four units, 11,294 (30%) in buildings of five or more, and 5,619 (15%) in single-family homes and other types.
How Somerville compares
Among the 23 towns we cover, Somerville ranks 22nd for oil heat (6% against an average of 20%), 2nd for natural gas (70% against 57%) and 12th for electric heat (19% against 19%). A few towns with a similar heating mix and housing age:
| Town | Oil | Gas | Electric | Median built |
|---|---|---|---|---|
| Everett | 12% | 67% | 18% | 1938 |
| Watertown | 13% | 67% | 15% | 1947 |
| Cambridge | 4% | 64% | 28% | 1950 |
| Boston | 7% | 56% | 32% | 1947 |
| Arlington | 18% | 59% | 18% | 1945 |
| Salem | 17% | 55% | 25% | 1938 |
By the numbers: Somerville is the 4th largest of the 23 towns by occupied homes (35,715). For every home on oil there are 11.3 on natural gas. Its median home year of 1938 is 14 years older than the 1952 average across these towns. 6,905 homes (19%) are electric, and 1,108 (3%) use propane or bottled gas.
Tune-ups for heating systems in Somerville
24,824 of 35,715 occupied homes in Somerville use gas. For them a tune-up is mostly about combustion, the heat exchanger and whether exhaust leaves safely.
In total, 28,134 of 35,715 homes (79%) burn gas, oil or propane: 24,824 gas, 2,202 oil and 1,108 propane. 23,483 homes (66%) are rented, and in those the owner of the building, not the person paying the heat bill, usually arranges service. Homes here are old: the median was built in 1938. Basements often hold equipment from several different decades.
Ready to book? Request a Somerville tune-up. What gets checked: furnaces, boilers.
If your boiler or furnace dies in Somerville
Gas is the default in Somerville (70%), and the rebate only follows if a Mass Save gas sponsor serves you. The gas bill tells you who that is. Rates and the January 1, 2027 drop are on the 2027 rebate page.
Get a replacement price in Somerville, or compare heat pump or a new oil boiler.
Where to go next
Estimate your rebate. Gas bill? Then this guide applies. Own a multi-family? Triple-decker heat pumps. A heat pump adds load, so check your panel.