First Midwest Bancorp Inc., parent company of First Midwest Bank, plans to purchase Northern States Financial Corp., holding company for Waukegan, Ill.-based NorStates Bank.

NorStates Bank operates eight offices in Lake County, Ill. and has approximately $500 million in total assets and $400 million in deposits, First Midwest said in a statement. The deal is subject to regulatory approval but First Midwest expects the deal to close before year’s end.

The purchase follows First Midwest’s announcement in late May that it planned to close 19 branch locations and reduce its workforce by 7 percent. The bank said its decision to reduce its branch offices is based on a growing number of its customers conducting their transactions either online or through mobile applications.

First Midwest is closing four locations in Northwest Indiana, which includes branches in Chesterton, East Chicago, Gary and Lowell. The remaining 15 locations are in Illinois and includes two in Chicago and the rest in Arlington Heights, Calumet City, Crest Hill, Crystal Lake, DeKalb, Lakehurst, Leland, Matteson, Moline, Naperville, Park Forest and Serena.

First Midwest will still have a presence in Northwest Indiana following the closure of the four Region locations. 

First Midwest will operate about 110 locations after the planned 19 are closed. The branch closures should be completed by the end of the year, the bank said.