Xcel Energy is set to become the largest office tenant in Denver’s River North submarket after the company inked a full-building lease for 220K SF at the soon-to-be-completed T3 RiNo building at 3500 Blake St.

The new building will serve as Xcel’s Denver headquarters for its roughly 1,200 employees, according to a press release, meaning the company will move out of its longtime home at 1800 Larimer St. Xcel's lease expires in 2025.

The relocation comes as Downtown Denver continues to reckon with changing office trends as hybrid work maintains a grasp on much of the office-using employment base.

River North has a relatively small office inventory, with most of the development in the area devoted to retail and multifamily uses.

T3 RiNo totals 235K SF, and Xcel is expected to move into the building in 2025. It is also one of Denver’s largest mass timber developments, a building method that produces a lower carbon footprint than buildings built with concrete and steel.

The features at T3 align with Xcel’s goals to produce 100% carbon-free electricity for its nearly 1.6 million electric and 1.5 million natural gas customers by 2050. Xcel's workforce is on a hybrid schedule, a company representative told Bisnow by email Wednesday.

“Being in a single-tenant building allows us to design collaborative workspaces for increasingly interconnected teams,” Xcel Energy-Colorado President Robert Kenney said in the release.

T3 RiNo is being developed by Hines, Ivanhoé Cambridge and McCaffery.