Spokane-based Washington Trust Bank has agreed to buy the 17-story Wells Fargo Center, at 601 W. First in downtown Spokane, from Inland Northwest Health Services.

The terms of the transaction, which is expected to be completed April 19, weren't disclosed. The Spokane County Assessor's Office lists the assessed value for the Wells Fargo Center at $21 million.

The 192,000-square-foot building is located across First Avenue from Washington Trust's headquarters building, at 717 W. Sprague.

Washington Trust, which markets itself at the largest privately held full-service commercial bank in the Pacific Northwest, is developing initial plans to occupy a portion of the building, Peter Stanton, Washington Trust chairman and CEO says in a press release announcing the transaction. INHS and Providence Health Care Foundation will move over the next three years to a new location from space they occupy in the building.

“We have grown significantly in recent years, and our downtown headquarters are no longer large enough to house all of our Spokane-based employees," Stanton says. "We have a strong culture, and we believe that bringing everyone together will help maintain that vibrant culture while also offering our employees Class A office space in downtown Spokane.”

Elaine Couture, CEO of INHS and executive vice president and chief executive of Providence Washington & Montana, says in the release that the sale will allow the organizations to focus on their core health care missions.

“Being able to sell this building to Washington Trust Bank keeps local ownership of one of the largest commercial office buildings in downtown Spokane,” Couture adds.

The name of the building will remain the Wells Fargo Center, and all current tenant leases will transition to Washington Trust. Spokane-based commercial real estate brokerage Kiemle Hagood, the long-time manager of the property, will continue to provide property management services.

Carl Guenzel, of Kiemle Hagood, brokered the transaction between Washington Trust and INHS.

The building currently is 85 percent occupied. In addition to INHS and Wells Fargo, current tenants include PotlatchDeltic Corp. and Shell Energy.

The building first opened in 1981, and INHS acquired the property in a foreclosure sale in 2012.

Washington Trust operates 43 branches in Washington, Idaho, and Oregon. The bank has 970 employees and assets exceeding $6 billion.