Key Takeaways
•Your first two bills of the year are estimates. They're built off last year's tax number, not a fresh look at your home's value.
•The winter bill is the one that moves. Your real FY2027 assessment and rate arrive by mail near year-end, and the whole year's increase lands in the last two bills.
•Two extra charges ride on top. The voter-approved high school debt exclusion and the Community Preservation Act (CPA) surcharge are separate from the base rate.
•Exemptions are yours to file. Nobody files them for you — confirm this cycle's deadline with the Board of Assessors.
# How Do Somerville Property Taxes Work?
Somerville bills property taxes quarterly. Your first fiscal 2027 bill is already behind you, and the second lands this fall. Confirm the due date printed on each bill.
Here's the part that surprises owners: your FY2027 home value has not been finalized yet. The first two bills are placeholders based on last year's net tax.
The real numbers arrive by mail near year-end. For FY2025, the Board of Assessors and Mayor's Office mailed the joint assessment-and-rate pamphlet on December 31, 2024, according to The Somerville Times. Expect a similar pattern this December.
Knowing which bill jumps is how you avoid a winter cash-flow shock.
Why Does the High School Borrowing Show Up on Your Bill?
Start with the levy — the total property tax the city collects from all owners combined. Massachusetts caps how much of that levy a city can raise each year, and voters can approve specific exceptions; the Board of Assessors can tell you how the current limit applies in Somerville.
Per the city's Information About Question 5 materials, Somerville voters approved one such exception for the new high school. Per the Somerville High School Building Project, the city borrowed $130.3 million. Debt service — the yearly loan payments on those bonds — runs from 2018 through 2054. Payments peak in 2027. That is right now.
Meanwhile the regular levy keeps climbing. The Somerville Times reported it rose from $245 million in FY2024 to $265 million in FY2025. The residential rate moved from $10.52 to $10.91 per $1,000 of assessed value — the dollar figure the city's Assessors put on your home for tax purposes, which is not the same as what a buyer would pay for it.
The city's FY2026 update shows the next step: Somerville plans to collect $279,376,680 from about $25 billion in taxable property value, at a proposed residential rate of $10.98 per $1,000.
Somerville FY2026 Property Tax Headline Numbers
A high-level snapshot of Somerville’s proposed FY2026 property-tax picture, combining levy, assessed value, tax rates, and the residential exemption savings.
FY2026
Property tax levy for FY26$279,376,680
Total assessed value of taxable property$25 billion
Residential tax rate (proposed)$10.98
Commercial tax rate (proposed)$18.94
Residential exemption tax savings$4,578
Source:FY2026 Property Tax Update
Commercial property is taxed at a higher proposed rate of $18.94, which shifts some of the burden off homeowners.
New growth — tax revenue from new construction and improvements, added on top of the cap — fell from $17.7 million in FY2024 to $14.1 million in FY2025, per the Chief Assessor's FY2025 Classification Hearing Report. When new growth slows, existing owners absorb more of the increase.
Which Quarterly Somerville Tax Bill Actually Changes?
Here's the cycle:
•Q1: preliminary, based on last year's tax.
•Q2: preliminary, using the same old math.
•Q3: the first "actual" bill, using your new assessment and rate.
•Q4: actual, using those same new numbers.
Because the first half of the year uses last year's math, the full increase from last year gets squeezed into the last two bills.
Your FY2027 numbers aren't set yet, but last cycle's FY2026 averages show the shape of it. Three-family owners faced the largest average tax change at $992, followed by single-family at $621 and two-family at $490. Condo owners averaged just $58.
Average FY2026 Value and Tax Change by Somerville Property Type
Compares average assessed value and average tax change across Somerville condos, one-family, two-family, and three-family properties. The tax-change figure includes the residential exemption per the source note.
| Category | Average Value FY26 | Average Tax Change |
|---|---|---|
| Condominium | $775,675 | $58 |
| 1 Family | $1,187,364 | $621 |
| 2 Family | $1,193,941 | $490 |
| 3 Family | $1,474,682 | $992 |
Source:FY2026 Property Tax Update
Do the division: $992 spread over four bills would be about $248 each. But it lands in two, so roughly $496 each. The same math on a single-family $621 change gives about $311 in each of the last two bills instead of about $155 across all four.
So three-family owners should brace hardest and condo owners least. The FY2027 dollar amounts will differ; the pattern is what carries over.
One more point: ask the Board of Assessors what valuation date your FY2027 assessed value reflects. It is not a prediction of what your home would sell for next spring.
What Are the Extra Charges on a Somerville Tax Bill?
What Is the High School Debt Exclusion?
This is the voter-approved charge tied to the borrowing above.
Projected High School Debt Exclusion Tax Impact by Property Type
Shows the projected additional annual property-tax impact of the Somerville High School debt exclusion across property types, from early borrowing years to peak impact.
Condo
Single-Family
Two-Family
Three-Family
| Series | Label | Value |
|---|---|---|
| Condo | Year 1 | $2 |
| Condo | Year 2 | $7 |
| Condo | Year 5 | $51 |
| Condo | Peak | $189 per year |
| Single-Family | Year 1 | $4 |
| Single-Family | Year 2 | $11 |
| Single-Family | Year 5 | $79 |
| Single-Family | Peak | $294 per year |
| Two-Family | Year 1 | $4 |
| Two-Family | Year 2 | $12 |
| Two-Family | Year 5 | $94 |
| Two-Family | Peak | $349 per year |
| Three-Family | Year 1 | $5 |
| Three-Family | Year 2 | $15 |
| Three-Family | Year 5 | $116 |
| Three-Family | Peak | $428 per year |
Source:Information About Question 5
The Building Project projects peak annual impacts of $189 for condos, $294 for single-family homes, $349 for two-family homes, and $428 for three-family homes. You cannot remove it by arguing your home is overvalued — confirm how it applies to your bill with the Board of Assessors.
What Is the CPA Surcharge?
Per the City of Somerville's Community Preservation Act page, the CPA program is a 1.5% surcharge on net property taxes, less the first $100,000 of property value, which is automatically exempt. It funds parks, historic buildings, and affordable housing, and it is folded into your quarterly bill.
Some owners — including low-income households and qualifying seniors — may be eligible for a full CPA exemption. Ask the Board of Assessors who qualifies, what income limits apply, and whether you must refile each year. And if you expect an exemption, still pay the surcharge by the due date. The refund comes later.
What If Your Mortgage Escrow Pays the Bill?
You may be thinking: my lender handles all of this, so the billing calendar is their problem. Mostly true — with two exceptions.
First, escrow — your lender collecting tax money with your monthly payment and paying the city for you — helps with timing, but it does not reduce the tax. Second, if your escrow analysis runs before the new assessment and rate are mailed, it works from old numbers. That is how escrow shortages happen.
So read the city pamphlet when it arrives, and check your mortgage statement after the winter bill posts. And remember: your lender does not file exemptions for you.
Why Can a Lower Tax Rate Still Mean a Higher Bill?
First objection: the residential rate barely moved, from $10.91 to $10.98 — about 0.6%, basically noise.
But the rate is only half the equation. Per the city's FY2026 Property Tax Update, Somerville's total levy still climbed to $279,376,680, and average tax changes ran from $58 for condos up to $992 for three-families — because assessed values moved, not the rate. A near-flat rate does not mean a near-flat bill, and whatever the change is, it arrives in only two of your four bills.
Second objection: Somerville's rate sits well below the state average, so owners here are getting off easy and the mechanics barely matter. Lamacchia Realty, citing Massachusetts Division of Local Services data, puts the 2026 statewide average single-family bill at $7,838 and the average rate at $12.18. Somerville's proposed residential rate is $10.98 — but values here run far higher: per the city's FY2026 Property Tax Update, the average single-family value is $1,187,364. Apply $10.98 per $1,000 to that value and the bill runs well past the $7,838 statewide average, before the debt exclusion and CPA surcharge are added.
What Should You Do Before the Spring Deadline?
If you own and occupy your Somerville home, start with the Residential Exemption. For FY2026 the city's Property Tax Update puts it at $4,578 in tax savings.
It is meant for owner-occupants, so confirm your eligibility with the Board of Assessors — especially if you rent the property out or closed mid-year, when the bill may still reflect the seller's status.
For the FY2026 cycle, The Somerville Times reported on March 30, 2026 that Wednesday, April 1 was the cutoff to apply for relief such as the Residential Exemption or Senior Tax Deferral. Confirm the FY2027 date with the Board of Assessors, and ask them as well about elderly, veteran, blind, and hardship relief.
Details are at somervillema.gov/assessing, or call the Board of Assessors' main line, listed on that page.
Your next move is simple. Read the year-end assessment pamphlet. Budget for a heavier winter bill. File any exemptions before the deadline the Assessors confirm. If you want help reading these numbers for a specific Somerville property, send over the address and we can walk through it line by line.
