Michael and Susan Dell are balancing their monumental philanthropic efforts with high-end real estate maneuvers. The multibillionaire couple—he the founder, chairman, and CEO of Dell Technologies, she cofounder and board chair of the Michael & Susan Dell Foundation—recently pledged an unprecedented $6.25 billion to seed 25 million children’s “Trump Accounts.” Simultaneously, they are streamlining their Boston property footprint.

The pair first listed their $34 million duplex penthouse atop the Four Seasons Private Residences at One Dalton Street in 2023, eventually reducing the asking price to $29 million before removing it from the market last year. Meanwhile, their second luxury holding in the city—a 59th-floor penthouse at the Millennium Tower, originally bought for $10.9 million—has just hit the auction block. Paramount Realty USA and Serhant Massachusetts are directing the sealed-bid event ending Oct. 29, with the minimum reserve price set at $6.5 million.

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On the 59th floor of the 60-story glass skyscraper completed in 2016 in the Financial District, the unit features three bedrooms, four full bathrooms, and a powder room. The roughly 4,100-square-foot layout showcases espresso-hued wide-plank white oak floors, over 11-foot ceilings, and expansive grid-style windows framing skyline, Charles River, and Boston Harbor views, along with a private outdoor terrace.

A foyer off a secured elevator landing leads to the large main gallery, flowing into a spacious living and dining area anchored by a linear, vent-free gas fireplace embedded in a black granite accent wall with an entertainment console on the opposite side. A butler’s pantry connects to a custom Christopher Peacock kitchen outfitted with rift-sawn oak cabinetry, honed Calacatta Extra marble countertops, an eat-in island, and Wolf and Sub-Zero appliances.

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Tucked away in a private corner, the primary suite features a walk-in closet/dressing area and a luxe bath wrapped in full-slab marble with a rounded-edge freestanding soaking tub. Two additional guest bedrooms, one staged with a workstation, each have their own bath and walk-in closet, and a designer powder room joins a dedicated laundry room.

A monthly $6,862 HOA charge includes access to a 24-hour doorman, two garage parking spaces, and a 20,000-square-foot private club offering Michael Mina dining, a 75-foot pool, wellness spas, and 24-hour white-glove concierge service.

Even with a shifting Boston portfolio, their ultra-luxury holdings remain vast. The Dells still own a 119-acre modernist compound known locally as The Castle in Austin, Texas, alongside a 4.3-acre oceanfront estate nicknamed the Raptor Residence in Kukio, Hawaii, and a $100 million duplex penthouse crowning Manhattan’s supertall One57.

Click here for more photos of the Boston residence.