GreatWesternBank.com 1

Making Life Great

Dear Customer,

Welcome to Great Western Bank.

Great Western Bank, Home Federal Bank and Infinia Bank are coming together to serve you as the new Great Western Bank. Were excited to have you as a customer. Know that our combined strength will help you build for your future with even greater confidence.

While the signs out front will change, you can still expect to receive the same prompt, efficient and friendly customer service that youve come to appreciate. As a Great Western Bank customer you will still do business locally, with bankers you know and trust.

Although the actual merger transaction is expected to occur earlier, Home Federal Bank and Infinia Bank will operate as a separate division of Great Western Bank until we combine our systems over the weekend of June 10, 20161. For now, it is business as usual. We will take great care to facilitate the smooth transfer of your accounts.

In this book, you will find information about Great Western Bank and answers to common questions you may have about this transition. Additionally, we have enclosed a disclosure booklet outlining the terms and conditions for Great Western Bank accounts. Once our operations are combined, these terms and conditions, including applicable fee schedules, will govern your account(s). We have also provided a table showing the changes, if any, that will occur with respect to your specific account(s). We urge you to review this information carefully.

In the coming weeks, you will receive additional information reminding you of key dates and events. Should you have any questions, please dont hesitate to contact your local banker.

Sincerely,

Ken KarelsPresident and Chief Executive OfficerGreat Western Bank

1 The systems conversion is expected to take place over the weekend of June 10, 2016, but is subject to the approval of applicable bank regulatory agencies and the shareholders of Home Federals parent company. There are other contingencies that may delay or prevent the merger as well. You will be notified if the merger is delayed or fails to happen.

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Great & Growing

Making Life GreatWeve been recognized as a Top 10 National Bank1 but were true to our roots as a community bank. Relationships matter.

Our mission is to Make Life Great by taking outstanding care of our customers and creating long-term relationships. For us, Making Life Great isnt merely a phrase we use to promote ourselves. Its a promise to make your financial life easier and more secure. Its helping you buy a home, start a business or plan your retirement. Its giving our employees an opportunity to grow and thrive.

The Midwest is our home and we understand the needs of business and agriculture that drive our local economies. Our Big Bank, Small Bank business model means we can provide services of a much larger bank, but still retain a customer-focused culture typically seen with smaller banks. We pride ourselves on providing the best of both. With Great Western Bank, you can bank where big enough and small enough meet.

Our commitment to the communities where we live and play is demonstrated through financial support, employee volunteerism and community leadership. Thats why youll see us serving meals at local shelters or volunteering our time at schools and civic organizations. Its our community too, after all, and its another way we Make Life Great.

1 See www.gobankingrates.com/banking/best-national-banks-2016/

What Makes Us Great Local bankers with deep relationships and decades of experience in their markets are empowered to make decisions that impact their customers. Great Western Bank has a proven track record of strong, disciplined growth and a highly efficient operating model. While adhering to our strong credit culture, we have built a well-diversified loan portfolio, which fuels the growth of our communities through personal, business and agricultural lending programs. Our history of producing strong earnings results, and our well capitalized standing, establishes Great Western Banks staying power today and into the future.

You have the peace of mind knowing the safe and sound place for your money is Great Western Bank.

Making Life Great

1935 Farmers and Merchants Bank is chartered in Watertown, SD.2003

Named changed to Great Western Bank.

2006 Acquired three branches from HF Financial Corp. and Security Bank (South Dakota).

Moved headquarters from Watertown, SD to Sioux Falls, SD.

2007 Great Western Banks Iowa charter (Iowa, Kansas and Missouri) and Great Western Banks Nebraska charter merge into Great Western Bank of South Dakota.

Acquired Sunstate Bank (Arizona).

2008 Purchased by National Australia Bank (NAB).2009

Acquired 20 offices of First Community Bank and one branch from Wachovia (Colorado).

2010 Acquired 10 branches of F & M Bank (Iowa) and 62 former TierOne offices (Nebraska).2014

Great Western Bancorp, Inc. launched Initial Public Offering and GWB shares began trading on the NYSE. 2015

NAB completes divestiture of GWB. GWB is 100% publicly traded.2016

Pending Acquisition of Home Federal Bank and Infinia Bank (South Dakota, North Dakota, Minnesota).

Great Facts Eighty years ago we were a small-town bank, but because of our sound and prudent banking practices (and a lot of hard work), we grew to become a leading regional bank. At heart, we are still that small-town bank now we have greater resources and capabilities.

As we come together, our combined bank will:

providecustomerswithaccesstomorethan170branchesacrossSouthDakota,NorthDakota, Minnesota, Nebraska, Iowa, Kansas, Missouri, Colorado and Arizona and over 20,000 surcharge-fee ATMs.

remaina100%publiclytradedcompanywithstocklistedontheNewYorkStockExchange under the trading symbol GWB (NYSE:GWB).

have$11.1billionintotalassetsand$1.6billionintotalcapital1.

takeprideinbeingthe7thlargestagribusinesslenderinthenation2.

betheemployerofchoiceforapproximately1,650GreatWesternBankemployees.

1 Based on preliminary unaudited proforma condensed combined balances as if the merger had occurred onDecember31,2015.

2AsofDecember31,2015.Source:ABA

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Great & Growing

Answers to Questions You May HaveWho is Great Western Bank?Great Western Bank is a full-service regional bank with branches across Arizona, Colorado, Iowa, Kansas, Missouri, Nebraska and South Dakota. With this acquisition, we will add operations in two additional states, Minnesota and North Dakota. We focus on relationship-based consumer, business and agribusiness banking and are recognized within our markets for our local, efficient decision-making.

The Great Western Bank difference begins with excellent customer service. Great Western Banks mission is to Make Life Great by taking outstanding care of our customers and creating long-term relationships.

Will there be any changes to my deposit account(s)?We have worked to minimize the changes. There will be some necessary product updates as we transition between the two systems. We will take great care to facilitate a smooth transfer of your accounts. Please refer to the disclosure booklet included for specific changes to your existing products.

Will my current checks still be honored? Yes. Continue to use your checks from Home Federal Bank or Infinia Bank. After June 10, 2016, when you run out of checks and need to reorder, please order checks through your local banker or at www.GreatWesternBank.com, unless you have been notified otherwise.

Can I still use my current personal or business debit and ATM card(s)?Yes. Continue to use your current debit and ATM card until its expiration date, at which time you will automatically receive your new Great Western Bank branded card.

Will my automatic payments and direct deposits (ACH) continue as scheduled?If you have set up automatic payments and direct deposits using a routing transit number (the nine-digit number located on the bottom of your checks), then yes, your transactions will continue as scheduled. The transition to Great Western Bank will be seamless.

What about automatic payments I have set up using my debit card?Automatic payments you have set up using your debit card will continue as scheduled.

Whats the plan with loan payment coupons? Continue to use your same loan payment coupon supply until further notice.

Can I bank at other Great Western Bank locations?We expect to consolidate the accounts from Home Federal Bank and Infinia Bank into Great Western Banks systems over the weekend of June, 10, 2016. Between now and then we ask that you utilize Home Federal Bank or Infinia Bank branches only. Beginning Monday, June 13, 2016, you can enjoy our expanded branch network.

How late can I make my deposits?Deposits made in-branch before the cut-off time will post as of the current business day.

Making Life Great

Does Great Western Bank offer 24-hour phone banking, online banking and mobile banking? Yes.Theseservicesareavailable24hoursaday,7daysaweekforyourconvenience. Great Western ebanking features a complete suite of online banking, mobile banking, bill payment and online statement services. Review the information in this booklet or visit www.GreatWesternBank.com for more information.

How will I access my current online banking account? You may soon notice some changes to www.HomeFederal.com and www.InfiniaBank.com. We will be deactivating certain pages that are no longer applicable. However, account access links will remain active until we combine our systems in June 2016. Continue to use these sites to access your account(s).

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