US Alliance Corp. has agreed to acquire Northern Plains Capital, according to a regulatory filing.

Holders of Northern Plains Capital common stock will receive, in exchange for their common shares, a number of shares of US Alliance's voting common stock, based upon the Dec. 31, 2016, book values of each of the two companies.

The transaction is subject to the approval of Northern Plains Capital shareholders, who will be asked to vote on the proposal during the company's annual shareholders' meeting to be held June 20, and the filing and effectiveness of a registration statement with the Securities and Exchange Commission.