Greenwood Village-based Bellco Credit Union is marking its 80th year in business on a growth tear.

In 2015, Bellco saw 8 percent growth in new members to 260,000, and this year it crested $3 billion in total assets – double the size of its next biggest competitor, according the Denver Business Journal’s annual Book of Lists.

The credit union, which opened its doors April 27, 1936 to serve the employees of the Bell Telephone System, will open its 22nd branch in Castle Rock in May. And the company is eyeing Louisville for its 23rd branch, said John Rivera, Bellco senior vice president of branch services.

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