San Francisco Office Vacancy Falls to 27.7 Percent as AI Companies Lease Large Blocks in SoMa

San Francisco’s office vacancy rate fell to 27.7 percent in the third quarter of 2026, down 1.5 points from the prior quarter and 6.6 points from a year earlier, according to CBRE figures reported by the San Francisco Examiner on October 14. The rate peaked at 36.9 percent in the third quarter of 2024. A separate Savills report, covered by The Registry and Allwork.Space, puts office availability at about 27 percent, down 640 basis points in a year.

The Numbers

CBRE reports vacancy and Savills reports availability, two different measures, but both point the same direction:

CBRE, Q3 2026 (via the Examiner): 1.3 million square feet of positive net absorption, the eighth straight quarter of more space being occupied than vacated; 2.7 million square feet leased in the quarter and 10.3 million year to date; 20 leases of 100,000 square feet or more signed so far in 2026, with nine more pending. The 2018 record was 29.

Savills, Q3 2026: 3.9 million square feet leased in the quarter, up 77 percent from a year earlier, and 12.1 million square feet through three quarters, compared with 8.1 million through the same point in 2025. Average asking rent was $70.31 per square foot, up 5.1 percent year over year, per Allwork.Space.

“Large lease transactions by expanding AI companies have been the catalyst for accelerating vacancy decline,” Colin Yasukochi, executive director of CBRE’s Tech Insights Center, told the Examiner.

Where the Leasing Is

All six of the quarter’s 100,000-square-foot-plus deals were signed by tech companies, and three were in SoMa, the Examiner reported. Named deals include Brex taking all of 270 Brannan St. (about 198,000 square feet), Airbnb leasing 122,000 square feet at 850 Brannan St., Cognition subleasing 182,000 square feet of former Cruise space at 333 Brannan St., and Sierra expanding to 351,000 square feet at 185 Berry St.

Asking rents in those areas are rising. CBRE put SoMa’s average asking rent at $82.57 per square foot, up 31.7 percent in a year, and Mission Bay’s at about $131, the highest on record there. Citywide, rents are up 11.1 percent since the 2024 low but remain 14.3 percent below their early 2020 peak.

What Comes Next

No new office buildings were delivered or under construction in the quarter, the 10th quarter in a row, per CBRE. Two projects, the 41-story office and hotel tower at 530 Sansome St. and 50 First St., aim to break ground within the next 12 months. Downtown buildings are also changing hands: SFGuide covered the sale of the old Federal Reserve Bank building at 301 Battery St. last week. For what to see in the area, see SFGuide’s SoMa neighborhood guide and things to do downtown.

Sources: San Francisco Examiner, October 14, 2026 (CBRE data); The Registry, October 2, 2026 and Allwork.Space, October 7, 2026 (Savills data).

Photo: 888 Brannan St. in SoMa. Dllu, CC BY-SA 4.0, via Wikimedia Commons.