April 29, 2016 <Primary First Name> <Primary Last Name> <Company> <Mailing Address> <City>, <State> <Zip> Dear <Primary First Name> <Primary Last Name>, First and foremost, I would like to take this opportunity to thank you for your business. The trust and confidence you’ve placed in our services here at Cetera/Great Western Investments & Insurance are genuinely appreciated. The merger of HF Financial Corp, Home Federal Bank’s holding company, into Great Western Bancorp, Inc., the holding company for Great Western Bank, is expected to close on or about May 13, 2016, subject to receipt of HF Financial stockholder approval and other customary conditions. In connection with the upcoming merger, I want to answer some questions you may have in regards to what this means for your investment accounts. Will this affect my accounts? Great Western Investments & Insurance will continue to operate business as usual and will continue to use Cetera as our broker/dealer. There will be no change in any of your investments. You will continue to receive the same statements and I will continue on as your agent/broker. In addition, I will maintain the same address, phone number and email if you need to reach me. How will I access my account online? The link to access your account online will be removed from our website. However, you will still be able to use the Cetera website to login to your account. Following the closing of the acquisition of Home Federal Bank, Great Western Bank will be operating with two broker-dealers for a period of time. Since we will be maintaining both relationships, we are required by regulation to remove any references to either broker-dealer in our advertising, including on our website. Accordingly, we will be deactivating the investment pages of our website. To access your account, please use the direct URL (website address) https://myaccount.iconnect2invest.com/bankr/login.do?webcontext=gwi Once you are on this site, the login process will remain the same. Your user name and password will not change. I suggest adding this URL to your browser’s Favorites or Bookmarks list. I would be happy to meet or discuss any questions that you may have about your account or this acquisition. Please feel free to give me a call to schedule a time to visit. Thank you again for the opportunity to serve you and your financial needs. Sincerely, <Officer> <Officer’s Title> <Officer’s Number> Great Western Investments & Insurance is a marketing name of Cetera Investment Services LLC, member IPC/FINRA. Securities and insurance products offered by Cetera Investment Services. Advisory services are offered by Cetera Investment Advisers LLC. Neither firm is affiliated with Great Western Bank, Great Western Financial Services, Inc. or their related companies. Investments are: • Not FDIC insured. • May go down in value. • Not financial institution guaranteed. • Not a deposit. • Not insured by any federal government agency. Advisory services are only offered by Investment Advisor Representatives. Registered Branch Office: 1235 N. Street, Lincoln, NE 68508. Filed by Great Western Bancorp, Inc. Commission File No. 001-36688 Filed Pursuant to Rule 425 Under the Securities Act of 1933 and Deemed Filed Pursuant to Rule 14a-12 Under the Securities Exchange Act of 1934. Subject Company: HF Financial Corp. Commission File No. 033-44383 Date: April 29, 2016