The annual property tax line on a Back Bay or downtown condo listing describes the seller's bill. If the seller lived in the unit as a primary residence, that figure probably already reflects Boston's residential exemption. A buyer who plans to use the same unit as a pied-à-terre or a rental will not get that credit, so the bill they inherit can be thousands of dollars higher on the same assessed value, in the same building, at the same tax rate.
That gap comes from how Boston chose to tax homes. It also shapes what a condo really costs to carry, depending on whether the buyer lives there full time.
The Number on the Listing Belongs to the Seller
Boston grants the exemption to owners who live in the property as their primary residence. It can apply to only one Boston parcel per owner. Eligibility depends on dates. For fiscal year 2027, which runs from July 1, 2026 to June 30, 2027, the city says owners who lived in the property as their principal residence on January 1, 2026 may qualify. There is also an expanded route for certain owners who bought and moved in between January 1 and June 30, 2026.
Boston's Assessing calendar explains why the timing matters. The first two quarterly bills of a fiscal year are preliminary, and each is half of the prior year's taxes. The third-quarter bill, issued in late December, is the first to show the new year's actual value and tax rate. The exemption is also applied on that December bill. A buyer who closes in the fall can therefore pay preliminary bills based on the seller's numbers before the bill that reflects their own status arrives.
A Flat Credit Paid For by a Higher Rate
The state statute, M.G.L. Chapter 59, Section 5C, lets a city exempt up to 35 percent of the average assessed value of all residential parcels. The exemption applies only to a taxpayer's principal residence, and the statute counts a condominium unit as a parcel. Boston uses the full 35 percent.
Because the exemption is pegged to an average, every qualifying owner gets the same dollar amount, whether the unit is a studio or a penthouse. For FY26, the city put the savings at up to $4,353.74. At the FY26 residential rate of $12.40 per $1,000 of value, that works out to about $351,100 of assessed value taken off the taxable total.
The money has to come from somewhere. The Massachusetts Division of Local Services, in its Municipal Finance Glossary dated July 2026, describes the trade-off. Granting the exemption "raises the residential tax rate and shifts the residential tax burden from moderately valued homes to apartments, summer homes, and higher valued homes." A second-home condo on Commonwealth Avenue fits that description, and so does an investor unit in a downtown tower. They pay the higher rate the exemption requires and get none of the credit.
What the Same Rate Means at Three Price Points
The figures below apply the FY26 rate and FY26 maximum exemption to three hypothetical assessed values. They show the mechanism only. FY27 figures have not been published yet.
| FY26 assessed value | Bill, not owner-occupied | Bill, owner-occupied with exemption | Share of bill the exemption removes |
|---|---|---|---|
| $900,000 | $11,160 | $6,806 | about 39% |
| $1,500,000 | $18,600 | $14,246 | about 23% |
| $3,000,000 | $37,200 | $32,846 | about 12% |
The table shows two things. At a value close to a typical Boston condo, the occupancy decision changes the annual bill by roughly 40 percent. At trophy values, a primary-residence owner keeps only a modest share of the bill, because the credit was sized for the average home and the higher rate applies to every dollar above it. For the urban buyers this practice works with, the gap between living in a unit and keeping it as a pied-à-terre narrows as the price climbs. It does not disappear.
Why the Gap Has Been Widening
The exemption shifts costs within the residential class. Since Boston's FY26 assessments, the residential class as a whole has been carrying a larger share of the levy.
The Boston Municipal Research Bureau reported in January 2026 that FY26 assessments, which reflect 2024 market activity, showed commercial values down $2.39 billion, or 3.9 percent, while residential values rose 2.7 percent. Residential property made up 69.2 percent of taxable value and paid 46.1 percent of the levy. BMRB called the residential share the highest in at least four decades, even though Boston applies the maximum shift onto commercial property that state law allows. In FY26, the City Council kept the commercial burden at the legal ceiling of 175 percent of residential. WBUR reported that the average single-family bill rose 13 percent, about $780, while bills on high-end office buildings fell 4.4 percent on average.
The exemption amplifies each change in the rate, and the amplification falls unevenly. In a parcel-level analysis of city assessment data for FY24 to FY25, State Sen. Will Brownsberger found that most downtown zip codes had median increases of 6.2 percent on non-owner-occupied residential bills, matching that year's rate increase. Increases on owner-occupied bills ranged from 4 percent to more than 14 percent "due to the leverage of the residential exemption." The same analysis found Boston's condo stock almost evenly split in FY25, with 36,212 owner-occupied units averaging $872,809 in value and 37,168 non-owner-occupied units averaging $881,302. About half of Boston's condo owners pay the full rate, and their units are valued about the same as those of the half that get the credit.
What Is Still Open Before the December Bill
The FY27 rate has not been set. The state has not changed the rules either, though there was an attempt. Mayor Michelle Wu asked the Legislature for permission to shift more of the levy onto commercial property for several years. WBUR reported that the state Senate rejected that plan 33 to 5 on January 15, 2026. The same day, according to GBH, the Senate voted 37 to 1 for an alternative that would let municipalities offer credits to qualifying households in years when residential levies rise more than 10 percent. That measure passed the Senate. It has not been confirmed as law.
The city's own budget points to the same pressures. Boston's FY27 budget assumes $40 million in new growth, less than FY26's actual figure. BMRB's April 2026 budget analysis said weak commercial conditions and falling commercial values continue to push the burden toward residential owners.
There is a counterargument. In an August 10, 2026 Boston Globe opinion piece, a director of the Small Property Owners Association cited Lincoln Institute of Land Policy research showing an effective tax rate of 0.51 percent on owner-occupied primary residences in Boston, fifth lowest among 53 major U.S. cities for a median-valued home. That figure measures owner-occupied homes, the group the exemption protects. It says nothing about the half of the condo stock that pays the full rate.
The city's FY27 exemption flyer suggested filing by mid-October so the credit would appear on the third-quarter bill. Applications stay open until April 1, 2027. This post is general information, not legal, tax or financial advice. Each owner should confirm eligibility and filing with the Assessing Department or a qualified tax professional.
A Few Direct Questions
Can one owner claim the exemption on two Boston condos? No. The city limits the exemption to one Boston parcel, and only to the owner's primary residence.
When will the FY27 rate and exemption amount be known? Both appear on the third-quarter bill, which the Assessing calendar schedules for late December. Until then, the most recent published figures are FY26's $12.40 rate and $4,353.74 maximum exemption.
Does a 2026 purchase qualify for FY27? The city describes an expanded route for certain owners who bought and moved in between January 1 and June 30, 2026. Anyone who closed later should confirm their status with Boston Assessing.
For buyers weighing a Back Bay, Beacon Hill or downtown condo as a primary home, a pied-à-terre or an investment, the carrying cost belongs in the pricing discussion from the first conversation. Robert Kinlin can work through how occupancy changes the numbers on a specific unit with you and your tax advisor before December's bill arrives. Let's Connect.
