First Hawaiian Bank said Friday that construction has begun on a new Mililani branch building on the site previously occupied by Jack in the Box in Mililani Shopping Center.

Once construction is complete, the current 3,750-square-foot Mili­lani branch will permanently relocate to the larger 4,250-square-foot site.

The new branch will be on the same side of the parking lot of the current Mililani branch at 95-390 Kuahelani Ave. Construction began a few weeks ago and is expected to be completed in the fall.

The current Mililani branch will remain open for business during the construction.

The new building will feature Wi-Fi, private consultation rooms and a spacious open lobby layout for enhanced customer service and engagement. A 24/7 vestibule will provide access to no-envelope deposit ATMs and night depository.

First Hawaiian, the state’s largest bank, has 49 branches in Hawaii, three on Guam and two in Saipan.