The regional banks announced the deal Tuesday.
Banner, based in Walla Walla, is the holding company for Banner Bank and Islanders Bank and has branches in Washington, Oregon and Idaho. Home Federal Bancorp Inc., based in Nampa, Idaho, is the holding company for Home Federal Bank, which has sites in Oregon and Idaho.
The combined company will have about $5.2 billion in assets, making it the fourth largest bank headquartered in the Pacific Northwest.
Mark Grescovich, Banner's president and CEO said the combination will help the company move toward its goal of becoming the community bank of choice in the Pacific Northwest. It significantly improves its market share in the Boise market and expands its presence in several key Oregon markets.
The boards of both companies have approved the deal, which still needs regulatory approval and approval by Home's shareholders.
Under the agreement, Banner will pay Home stockholders and option holders a total of $87.6 million in cash and 2.9 million shares of Banner common stock, subject to price collars. Based on Banner's closing price of $37.66 on Tuesday, the deal has an estimated total value of $197 million.
Banner expects the deal will immediately boost its earnings, excluding one-time transaction expenses.
The companies expect the deal will close in the first quarter of 2014.
Shares of Banner added 33 cents to close regular trading at $37.66 but were unchanged in after-hours trading following the announcement. Shares of Home Federal fell 13 cents to close at $12.65 and were also unchanged after hours.