Property tax and assessed value in central Worcester County

This page publishes no tax rate for any town, on purpose. A Massachusetts rate is set annually, and one copied into an article is wrong the moment the next is certified — worse than no number, because it still reads as current. What follows is how the assessment is built, what the rate is applied to, what else lands on the same bill, and where to look up a specific parcel.

What the assessment is, and what date it speaks for

Massachusetts assessors value property at full and fair cash value as of January 1 preceding the fiscal year. The municipal fiscal year runs July 1 to June 30, so a fiscal year 2027 assessment is an opinion of what the property was worth on January 1, 2026, and it was built largely from sales that closed in the calendar year before that.

That lag is the reason assessments and sale prices diverge. An assessment is a mass appraisal — a valuation model applied to thousands of parcels at once from a fixed date — not an individual appraisal of your house. Values are recertified on a five-year cycle audited by the Department of Revenue, and in between assessors adjust for physical changes to the tax base such as new construction, additions and demolitions.

Assessed value is not market value, and is not a price

Three numbers get confused constantly, and they answer different questions.

• Assessed value — what the town concluded, as of a past January 1, for the purpose of apportioning a tax levy.
• An automated online estimate — a model output from a company that has never been inside the house.
• Market value — what a comparable property actually sold for, verified sale by sale.

Only the third is evidence of price, and even then only closed sales count. How the different home-value measures are produced takes that apart properly, and what a valuation on your own home involves is the place to start if you are pricing rather than budgeting.

Buying at a price above or below the assessment does not reset it. Your purchase does not automatically become next year's assessed value, and a seller's current tax bill is not a promise about yours.

Where the rate comes from, and why a lower rate can mean a higher bill

The rate is not chosen for its own sake. A town votes a budget, determines how much must be raised from property tax — the levy — and the rate falls out of dividing that levy by the town's total taxable assessed value. When total valuation rises faster than the levy, the rate goes down while individual bills go up. A rate change alone tells you nothing about the direction of your bill.

Two constraints sit on top of that. Proposition 2½ caps the total levy at 2.5% of the town's total assessed valuation and limits the annual increase in the levy limit to 2.5% plus certified new growth, with overrides and debt exclusions requiring a ballot vote. Separately, a community may adopt classification, shifting a larger share of the levy onto commercial, industrial and personal property and producing a split rate. A town with a split rate has more than one rate, so make sure the figure you looked up is the residential one.

Estimating the base tax for one parcel

The arithmetic is simple once you have both inputs from the right fiscal year:

assessed value ÷ 1,000 × the residential rate for that fiscal year = base annual tax

To show the shape of it with hypothetical inputs that are not any town's figures: an assessment of $500,000 and an illustrative rate of $10.00 per $1,000 give 500 × 10 = $5,000 for the year, billed across four payments in a quarterly town. Substitute the assessment from the record card and the rate you looked up yourself — never a rate from an article, including this one.

Exactly where to look up a specific parcel

1. The town assessor's office or online database holds the property record card: living area, year built, room and bath count, lot size, and the assessed value by fiscal year. Check the card against the house — an assessor carrying a three-bedroom on a property marketed as four is a question worth asking before you offer.
2. The assessors also publish the certified rate for the current fiscal year, and they are the only source that knows whether the next one has been certified yet. The Department of Revenue's Division of Local Services maintains statewide rate data by municipality and fiscal year, which is where to confirm what you were told.
3. The registry of deeds shows what the property last sold for and what liens run with it. Upton, Westborough, Northbridge, Grafton, Mendon and Millville record at the Worcester District Registry of Deeds. Hopkinton is in Middlesex County and records at Middlesex South in Cambridge. Both search free at MassLandRecords.
4. The collector or treasurer answers whether anything is outstanding on the parcel — which is a different question from what the tax is.

What else is on the bill and is not the tax rate

• A Community Preservation Act surcharge, in towns that have adopted it under MGL c.44B. It is a surcharge on the levy against your property, statutorily capped at 3%, and towns choose their own exemptions — commonly the first $100,000 of valuation and full exemptions for qualifying low-income owners.
• Betterments and special assessments. A betterment is not tax. When a town builds an improvement benefiting a limited area — most often a sewer or water extension — it may assess the benefited properties under MGL c.80. That becomes a recorded lien, usually apportioned over years with interest, and may appear on the bill as an installment. Ask whether a balance remains and who pays it at closing; a buyer who assumes the seller handled it can inherit years of payments.
• Municipal charges liens. Unpaid water, sewer or other municipal charges can be certified to the assessors and added to the real estate tax on the property they relate to.
• Statutory exemptions and deferrals under MGL c.59 §5 reduce a particular owner's bill where that owner qualifies and applies. They attach to the person, not the house, so they do not transfer with a sale. The assessors keep the list of clauses the town has adopted and the filing requirements.

Preliminary bills, actual bills, and the calendar

In a quarterly-billing community the first two bills of the fiscal year are preliminary — estimates issued before the new rate exists — and the second two are actual, issued once the rate is certified, carrying the year's assessment and the full-year reconciliation. Comparing a preliminary bill to last year's actual will mislead you every time. Semiannual towns run a different calendar; ask the collector which yours uses.

If you believe the assessment is wrong

An abatement application goes to the town's board of assessors, on the state form, by the due date of the first actual tax bill for that fiscal year — commonly February 1 in a quarterly-billing town. That deadline is statutory and assessors cannot extend or waive it, so a late application forfeits the right entirely. Pay the tax as assessed while the application is pending to protect your appeal rights, and confirm the current filing window with the assessors before you rely on any date, including that one.

An abatement argues the assessed value is wrong — usually from a physical error on the record card, or from comparable sales as of the relevant January 1. It does not argue the rate is too high. Appeals beyond the assessors go to the Appellate Tax Board, where the deadlines are worth an attorney's time.

Where this fits

Tax is one line in the annual cost of a house, and rarely the line that surprises people. The rest of what ownership costs here covers insurance, fuel, water and septic, solid waste and capital items, and the buyer's process and the public records behind it sets out where each number comes from. How this site is researched, and how to correct it explains why there is no rate on this page.