Brex is going all in on San Francisco. The fintech firm has signed on to take every last square foot at 270 Brannan Street in SoMa, locking in a lease that stretches close to a decade. It is a striking turnabout for a company that ditched its Financial District headquarters in 2021 in favor of a headquarterless, remote-first model, and it builds on Brex’s partial return to the same address last year. In a downtown still wrestling with office vacancies, one tenant claiming an entire building is hard to ignore.
The expanded deal, inked earlier this month, boosts Brex’s footprint at 270 Brannan from a partial presence to full control of the building, according to the San Francisco Chronicle. The paper reports that JLL brokers Charlie Hannafin, Chris Roeder and Jack Churton negotiated the lease on behalf of landlord Mitsui Fudosan America, and that Brex’s commitment runs for nearly 10 years.
Brex Plants Its Flag Back Home
“San Francisco is Brex’s home, and we’re excited to be here as we enter our next chapter,” Ben Gammell, the company’s president, told the San Francisco Chronicle. The Chronicle framed the timing of the bigger lease around Brex’s April acquisition by Capital One and the company’s push to build out in-office teams as it ramps up its AI work.
Office Market Tries a Comeback
San Francisco’s office market, which has spent years as a national cautionary tale, is starting to show some momentum. Commercial real estate firm CBRE reports that the city notched its seventh straight quarter of positive net absorption in the second quarter of 2026, with downtown vacancy drifting down to about 29.2 percent.
According to CBRE, AI-focused startups did a lot of the heavy lifting, accounting for nearly 1 million square feet of net absorption in the quarter. Overall leasing volume reached almost 3 million square feet, while tenant demand hit a record 8.9 million square feet, as companies went back to the market to shop for space.
How Brex Ended Up Back in SoMa
Brex walked away from its downtown headquarters in 2021 as it shifted to what it called a headquarterless model, according to CoStar News. That strategy was emblematic of the pandemic-era tech retreat from San Francisco’s core.
By 2025, though, Brex had quietly started rebuilding a physical foothold in the city with a roughly 100,000-square-foot lease at 270 Brannan, part of a broader rebound of startups and AI players into SoMa, as detailed by Hoodline.
A Bigger, Bolder Bet After Capital One Deal
The decision to take the entire building followed Brex’s acquisition by Capital One in April 2026. Capital One confirmed the deal in a company press release, positioning Brex inside a much larger financial institution.
With that backing, longer-term office commitments suddenly look more manageable for a company that once prized maximum flexibility over fixed overhead. Analysts say the capital and stability that come with a big-bank parent can make it easier to lock in space for planned growth rather than hopscotching between shorter, smaller leases.
What 270 Brannan Holds
Owner Mitsui Fudosan America markets 270 Brannan as a roughly 183,000-square-foot, LEED-certified Class A property in the heart of SoMa, according to the building’s property profile. Earlier reporting indicated the initial Brex lease could eventually accommodate around 500 employees, suggesting the company intends to pack the address with significant engineering and AI teams, as noted by CoStar News.
For San Francisco, Brex’s all-in move is a clear signal that large, concentrated leases are not relics of the pre-pandemic past, especially as AI and finance firms bulk up local headcount. CBRE has tracked the same trend citywide in its latest quarterly report.
What comes next is worth watching: how Brex configures its teams inside 270 Brannan, what build-outs it requests from Mitsui, and whether other AI-driven tenants decide to follow suit and grab big blocks of space in SoMa instead of dialing into yet another video call from home.
