Together AI San Francisco Headquarters Leases 150K SF

Together AI is accelerating its Bay Area footprint as it moves toward a full San Francisco headquarters in Showplace Square. On April 16, 2026, the company announced a lease for roughly 150,000 square feet at 2 Henry Adams Street, a six-year commitment that will reposition the startup’s presence in one of San Francisco’s most active AI districts. The news comes as the San Francisco office market continues to rebound from the pandemic-era slowdown, with large blocks of space changing hands as AI employers scale up their operations in the city. Together AI’s relocation and expansion reflect both the company’s rapid growth trajectory and the broader trend of AI tenants driving significant lease activity in Showplace Square and neighboring neighborhoods. This article anchors the event date to April 16, 2026 and ties the lease to publicly reported sources, while placing the deal in a broader market context for readers of the SF Bay Area Times. According to the San Francisco Business Times, the lease covers 150,000 square feet and signals a major expansion from the company’s earlier footprint in the area. (bizjournals.com)

The opening move arrives as Together AI, a player in the AI-native cloud space, has demonstrated momentum beyond real estate. The firm’s path to 150,000 SF in San Francisco builds on recent fundraising and product milestones that positions it as a scalable provider of AI infrastructure and open-source model hosting. In February 2025, Together AI announced a $305 million Series B round (led by General Catalyst and co-led by Prosperity7), a signal of investor confidence at scale. The company’s own announcement highlights its aim to accelerate its AI acceleration cloud for open-source and enterprise AI, underscoring the strategic importance of growth in both capital and physical footprint. This fundraising milestone — and the subsequent SF lease — are connected in the broader narrative about Together AI’s ambitions and the Bay Area’s evolving AI office landscape. The funding news and the HQ lease, when viewed together, illustrate a company that is pursuing both capital-intensive infrastructure and a substantial local presence to support a global customer base. The fundraising detail is based on Together AI’s own release. (together.ai)

Section 1: What Happened

Lease specifics and location

Together AI leased approximately 150,000 square feet at 2 Henry Adams Street in San Francisco’s Design District, commonly referred to as Showplace Square. The space is being taken on a six-year term with occupancy slated for this summer, and the deal represents a significant expansion from the company’s earlier footprint near the Mission/SOMA corridor. Market observers describe 2 Henry Adams Street as part of a historic brick-and-timber building complex that has drawn attention from tech tenants as SF’s AI office market strengthens. The San Francisco Business Times’ reporting on the lease is the primary public source detailing the size, term, and occupancy timeline, and it is echoed by industry outlets covering the broader market dynamics. (bizjournals.com)

Building context and district dynamics

The Henry Adams Street building is part of a blocks-long wave of AI tenants clustering in Showplace Square and the surrounding Showplace/Potrero submarket. CoStar’s coverage emphasizes two floors within a roughly 329,000-square-foot building, highlighting the scale of the space Together AI is acquiring and the strategic location within SF’s post-pandemic office market. The lease’s timing aligns with a broader trend in early 2026 where multiple AI companies were pursuing larger-than-average footprints in San Francisco, signaling a more confident revival of big-block deals in the city. (costar.com)

Corporate milestones linked to the deal

Together AI’s public-facing milestones include its February 2025 Series B, which the company framed as a major step toward expanding its AI acceleration cloud for open source and enterprise AI. That milestone helps contextualize the SF lease as part of a broader growth plan that couples capital deployment with a physical expansion to support a growing developer and enterprise base. The company’s own press materials document the fundraising and strategic direction, while local market reporting confirms the lease sizing and location. (together.ai)

Timeline of related developments

2023: Together AI’s SF footprint began with a small local presence, expanding to new space over time as the company scaled. Market reporting notes that the company’s footprint grew from tens of thousands of square feet in the early phase to much larger blocks in 2026, illustrating a rapid expansion trajectory. This growth is documented in market recaps and industry notes that track SF AI leasing activity and show the company’s evolving footprint in the Design District. (bisnow.com)
2024–2025: Together AI publicly publicized its product and market milestones, culminating in the February 2025 Series B fundraising, which the company framed as acceleration of its AI cloud and model-hosting capabilities. The fundraising narrative provides context for the SF lease as part of a cohesive growth plan that couples capital with a larger SF space commitment. (together.ai)
April 2026: The SF lease for 2 Henry Adams Street is publicly reported by multiple outlets, with the SF Business Times providing the baseline figures and occupancy timeline, and industry trackers corroborating the deal size and term. The Real Deal and CoStar reporting further confirm the magnitude of the lease and its place within SF’s AI leasing wave. (bizjournals.com)

Section 2: Why It Matters

Impacts on San Francisco’s AI ecosystem

Together AI’s move to 2 Henry Adams Street signals more than a simple office relocation. It marks a tangible step in the Bay Area’s re-emergence as a gravity center for AI infrastructure and application development. The Henry Adams Street facility provides the scale required to host advanced GPU clusters and enterprise workloads, aligning with the company’s stated strategy to deploy an AI-native cloud for open-source models and for enterprise-grade AI workloads. Industry observers note that Showplace Square and the adjacent Design District have become an attractive cluster for AI and high-tech tenants, reinforcing SF’s role in AI innovation and talent access. The leasing activity around 2 Henry Adams Street, including the reported 150,000 SF block, underscores a broader trend of large developers and landlords pursuing long-term leases with leading AI companies in a neighborhood that fits well with the city’s existing tech ecosystem. (costar.com)

Economic and employment implications

The SF Bay Area remains a magnet for AI startups and established AI firms seeking a physical presence to complement their digital capabilities. The lease at 2 Henry Adams Street not only expands Together AI’s local footprint but also contributes to San Francisco’s office market recovery, particularly in Showplace Square, where several AI tenants have pursued sizable blocks in a relatively tight market. Market analyses of early 2026 show that large leases in SF consolidated in specific submarkets, a pattern that resonates with the 2 Henry Adams Street transaction. Analysts and brokers have highlighted the submarket’s ability to absorb large blocks and support AI development teams, data operations, and cloud infrastructure facilities that require robust electrical and data-center-grade capabilities. While the details of the lease are not fully disclosed in every report, the available data points clearly indicate a substantive, multi-floor commitment in a district that has become synonymous with SF’s AI renaissance. (f.tlcollect.com)

Strategic significance for Together AI and similar firms

From the company’s perspective, the SF headquarters move is aligned with a broader strategy to scale the AI-native cloud and to meet growing customer demand for open-source model hosting, enterprise performance, and scalable GPU-based inference. The fundraising milestone in 2025 demonstrates the capital velocity behind a company pursuing aggressive product development, while the 2026 SF lease demonstrates the necessary physical footprint to support product deployment, partner integrations, and customer onboarding at scale. For other AI infrastructure players and startups, the SF lease serves as a reference point for what it takes to build a substantial presence in one of the world’s most competitive AI markets: a large, well-situated space in a district with a track record of attracting cloud-oriented AI enterprises. The market signals from CoStar and local outlets reinforce the view that Showplace Square is now a core node in SF’s AI office map. (together.ai)

Policy, governance, and market risk considerations

As SF’s AI office expansion continues, policymakers, investors, and company executives will watch how the market balances demand with infrastructure capacity and energy supply. The Henry Adams Street lease spotlights a growing need for robust electrical and data infrastructure to support large-scale AI workloads. Market reports in early 2026 indicate a surge in large-block leasing activity compared with the preceding years, implying a shift in risk tolerance from both tenants and landlords. The broader governance question — how to sustain AI growth while maintaining talent pipelines, housing affordability, and urban infrastructure — remains in focus for SF Bay Area leaders and readers of SF Bay Area Times. (f.tlcollect.com)

Section 3: What’s Next

Occupancy and integration timeline

With occupancy slated for this summer, Together AI will begin integrating its teams and operations into the 2 Henry Adams Street facility in a phased manner. The building’s layout supports multi-floor operations, enabling the company to deploy GPU clusters and enterprise-grade AI workloads across two floors, as described in market coverage. While specific internal timelines may evolve, the house view suggests a gradual ramp as teams relocate, IT systems are migrated, and security and compliance protocols are established for a broader AI cloud environment. Market trackers note that occupancy of this size typically aligns with staged onboarding and a transition plan to prevent service disruption for customers and partners. (costar.com)

What to watch in the SF AI office market

Continued large-block activity in Showplace Square and nearby submarkets, especially among AI infrastructure and cloud-focused firms. Observers expect more announcements as demand for space that can host GPU clusters and AI workloads remains high. CoStar’s reporting and regional market analyses show a pattern of multi-floor deals across key SF districts, suggesting further tie-ins between real estate cycles and the pace of AI product development. (costar.com)
The balance between landlord incentives and tenant commitments in a post-pandemic SF market. As this lease demonstrates, AI tenants are willing to commit to sizable, multi-year deals when the location aligns with talent access and ecosystem maturity. Market reports from early 2026 show a steady appetite for large leases, especially in districts that have demonstrated long-term resilience. (f.tlcollect.com)
The interplay between fundraising milestones and real estate expansion. Together AI’s 2025 Series B funding underscores the capital velocity behind a company expanding infrastructure, product development, and eventually its SF footprint. Readers should watch whether additional rounds or strategic partnerships accompany future consolidations of space in Showplace Square or nearby districts. The company’s own fundraising release provides a baseline for this narrative. (together.ai)

Timeline of next steps for Together AI and SF observers

Summer 2026: Occupancy and initial integration into the Henry Adams Street site occur, with teams gradually relocating and setting up GPU clusters and cloud infrastructure to support customer workloads.
Late 2026–2027: Capacity planning and scale-out considerations may drive further space optimization or expansion in the same submarket, depending on product demand, hiring velocity, and performance requirements.
Ongoing: The AI office market in San Francisco will continue to be watched for new large-block deals, which will shape the city’s competitive positioning relative to other AI hubs in the U.S. and globally.

Closing

The announcement of Together AI’s San Francisco headquarters at 2 Henry Adams Street marks a notable milestone for both the company and the Bay Area’s AI ecosystem. It confirms a trajectory in which Open Source–oriented AI infrastructure firms are not merely testing new spaces but committing to multi-year, multi-floor footprints in neighborhoods that have become synonymous with AI innovation. For SF Bay Area readers, the development signals a stabilized, long-term confidence in the city as a global center for AI engineering, cloud infrastructure, and data-driven product development. As occupancy proceeds and teams migrate, Together AI’s SF headquarters will serve as a focal point for evaluating how the region balances rapid technology growth with the practical demands of urban infrastructure and housing affordability. For ongoing updates on this story, keep an eye on both local business coverage and the company’s own press materials as the lease unfolds and operations scale.

The Bay Area Times will continue to report on Together AI’s progress, its contributions to SF’s AI cluster, and the evolving role of the Design District in shaping the city’s technology economy. Readers can expect follow-up coverage on how the Henry Adams Street site integrates with SF’s broader AI ecosystem, including any additional space announcements or new partnerships that arise from this milestone.