Columbia Banking System Inc., which operates Columbia State Bank, has completed an acquisition of West Coast Bancorp, parent company of West Coast Bank.

Columbia operates 157 branches in 38 counties in Washington and Oregon. Its Bellingham location, at 211 E. Holly St., serves as a commercial lending base for Whatcom and Skagit counties.

With the merger, Columbia’s total assets now exceed $7 billion, according to the company.

“We are delighted to welcome the customers, employees and shareholders of West Coast to Columbia,” said Melanie J. Dressel, president and CEO, in a press release. “The merging of Columbia and West Coast moves us significantly toward our stated objective of being the leading Pacific Northwest regional community bank. The complementary aspects of the companies’ businesses, including customer focus, geographic coverage, business orientation and compatibility of management and operating styles, makes the merger a natural fit.”

Columbia also appointed David A. Dietzler, a former director of West Coast, to serve on the boards of directors for the Columbia company and Columbia State Bank.

Columbia is headquartered in Tacoma. The company is online at www.columbiabank.com.