"organization expanded" is a correct and usable phrase in written English.
You could use it when talking about an organization that has grown in size, scope, or influence. For example, "The organization expanded rapidly in the last decade, growing from five employees to fifty."
The organization expanded to Oregon and Indiana in 2012.
The organization expanded into social services and education.
Last year the organization expanded from Fridays only to also include Thursdays from March through September.
A decade ago, the organization expanded to parts of rural Maharashtra abutting Mumbai, the state's capital.
In the years that followed, the organization expanded its work to include events like a yearlong campaign in 1992 called New York Celebrates the Arts, which proclaimed the city's cultural pre-eminence and announced events in brochures and banners in airports and train stations.
The construction of a top-down promoted organization expanded the coverage of labor arbitration institutions and enriched the resources of institutions.
Woolson offered a postmortem: "It's really a case of an organization expanding too far too fast," he said.
On the surface, the goal of the Kravis Prize is to help a service-oriented organization expand what it is doing.
December 16 2012 December 18 201212 Alice Tully Hall's resident organization expands to orchestral size for its annual performances of Bach's joyous concertos, a longtime holiday tradition.
The grant should help the organization expand its mission running equality-based schools.
"They start to work with our individual consultants, then over time our footprint within an organization expands," Lepe told me.
