In Q3 2025, Boston’s multifamily sector demonstrated solid supply and demand fundamentals, with 294,142 units in inventory and 13,117 units under construction. Net absorption reached 2,600 units—the strongest quarterly figure of the year—reflecting steady in-migration and sustained renter demand. Deliveries of 2,800 units slightly outpaced absorption, keeping vacancy unchanged at 6.2%, a level that remains favorable compared to national averages.

Rents continued to show resilience, with the metro-wide asking rent averaging $2,930 per month. Annual rent growth held at 1.2%, supported by strong performance in submarkets like South Boston/Seaport, which posted the highest rent growth rate at 4.9%. With leasing activity matching the pace of new supply and demand anchored by Boston’s Tier 1 economy, the market remains well positioned for stable rent growth and below-average vacancy in the quarters ahead.

 

Key Findings

• Absorption has risen consistently throughout this year, with the third quarter noting the highest level at 2.6K units absorbed.
• Seaport District and Kendall Square are standouts for biotech employment, with the addition of new lab space.
• Rent stabilization is not currently in place across the metro, but Mayor Michelle Wu is seeking to bring it back, which could cap annual rent increases at 6%.

 

Boston Multifamily Supply & Demand Dynamics

Source: CoStar Group, Inc.

Greater Boston MSA Demographics

Source: CoStar Group, Inc.

• Unemployment Rate: 4.3%
• Current Population: 5,068,979
• Households: 2,015,015
• Median Household Income: $116,587

Greater Boston MSA Population, Labor, & Income Growth

Source: CoStar Group, Inc.

Greater Boston MSA Construction

Boston currently has approximately 13,000 units under construction, representing 4.5% of total inventory. Activity is heavily concentrated in
the Somerville/Charlestown and South Boston/Seaport submarkets, which together account for more than one-third of all projects underway. The Chelmsford/Tyngsborough/Townsend submarket also experienced a notable influx, with construction equaling 21.5% of existing inventory. A shift in product mix is evident as well, with Class B developments making up a growing share of the pipeline. Roughly 4,726 units, or about 30% of all units underway, fall within this tier, reflecting a broader transition as institutional investors pause Class A projects.

 

Unit Construction Starts

Source: CoStar Group, Inc.

Units Under Construction

Source: CoStar Group, Inc.

Sales

Boston’s multifamily investment activity remained resilient in Q3 2025, underscoring the market’s status as a premier national destination for capital. Sales volume reached $904 million, extending a streak of quarterly activity above $850 million and pushing year-to-date transaction levels well ahead of historical averages. Over the past 12 months, more than 13,800 units have traded, surpassing the five-year annual benchmark of roughly 11,700 units. Pricing continued to reflect Boston’s premium positioning, with assets averaging $450,000 per unit, double the national figure of $230,000 per unit, while cap rates held steady at 5.1%. Buyer activity was led by private capital pursuing mid-sized deals, complemented by institutional investors selectively targeting large-scale, core assets. This balance of participants highlights both the market’s liquidity and its enduring appeal for long-term growth.

 

Boston Multifamily Sales Volume

Source: CoStar Group, Inc.