Mesirow Financial has officially taken over Twenty20, the 20-story apartment tower at 20 Child St in Cambridge Crossing, paying $218 million for the privilege, according to public records. The 355-unit high-rise, which opened in 2015, traded hands this week and now folds into the Chicago firm's growing multifamily portfolio. The sale was listed on Feb. 10 and has since been recorded in county filings.
Deal details
As reported by Bisnow, Mesirow bought Twenty20 from PGIM Real Estate for $218 million, roughly $21 million more than PGIM shelled out in 2015. Public records cited by Bisnow show that Walker & Dunlop provided a $139 million mortgage to help finance the purchase. The transaction surfaced in county filings this week, lining up with the reported closing timeline.
What Mesirow bought
Twenty20 is a 20-story, 355-unit community offering a mix of studios, one-bedrooms, two-bedrooms and three-bedrooms, plus about 8,625 square feet of ground-floor retail space. The building’s listing on Apartments.com highlights a fitness center, a rooftop terrace, on-site pet grooming and a full-time concierge, a fairly textbook amenity lineup for the modern Cambridge renter. CoStar data indicate the community was about 98% leased in the most recent report, which does not exactly scream “distressed asset.”
Neighborhood and transit
The tower sits inside the 43-acre Cambridge Crossing development, a mixed-use campus that blends offices, labs, housing and retail, and has become a magnet for life-sciences tenants. As Bisnow notes, major employers in the immediate orbit include Sanofi and Bristol Myers Squibb, and the building is within walking distance of the Lechmere MBTA station. Nearby Park 151 has posted strong leasing, reinforcing the idea that renters who work in biotech and pharma are more than willing to pay for a short commute.
Why investors are paying up
Mesirow has been steadily expanding its apartment holdings. The firm closed a $1.245 billion real estate fund in May 2025 that targets value-add multifamily, according to a company press release, giving it plenty of dry powder for deals like Twenty20. CoStar has reported that Cambridge Crossing’s concentration of lab and pharma jobs has helped keep nearby multifamily properties highly leased, a dynamic that likely factored into Mesirow’s willingness to pay up. The acquisition is another indication that institutional buyers are still pursuing stabilized rental assets in high-demand Boston submarkets despite the sting of higher borrowing costs.
Brokers and next steps
Industry reporting indicates that CBRE handled marketing for the sale and brought Mesirow to the table while the asset was on the market. The Real Reporter first spotlighted the potential deal back in December and noted CBRE’s role in the process. For current residents, day-to-day life is unlikely to change much in the short term, as new owners typically keep operations steady while they sort out any renovation or upgrade plans.
For Cambridge, the sale underlines persistent investor appetite for rental housing near the city’s life-science cluster and shows that buyers with fresh capital are still willing to pay premiums for stabilized, transit-accessible buildings. We will continue watching county filings and leasing reports as Mesirow folds Twenty20 into its portfolio and decides what, if anything, to tweak at the property.
