First Interstate BancSystem : 2024 Corporate Responsibility Report

Investing in

our communities.

2024 Corporate Responsibility Report

TABLE OF CONTENTS

Letter to Stakeholders	5
Executive Summary	6
Social Report	8
Employees	10
Clients	23
Communities	30
Environmental Report	62

Governance Report

Conclusion

70

78

SUMMARY

For 55 years, First Interstate Bank has been woven into the fabric of hard-working communities as a source of strength and stability. When opening our first branch in Sheridan, Wyoming, in 1968, commitment to community was established as a core value and priority. That commitment is stronger than ever today and shines through in over

300 banking offices across 14 states. We are driven by our values to do right by all our stakeholders - employees, clients, communities, and shareholders. Each day, we strive to center and strengthen those important relationships, and we dedicate ourselves and hold ourselves accountable to sound environmental, social, and governance practices.

3 | Corporate Responsibility Report

INTRODUCTION

Remaining steadfast in our commitment to community.

The 2024 Corporate Responsibility Report for First Interstate BancSystem, Inc. delves into the priorities, initiatives, and principles that shaped our franchise in 2023. As we settled into new markets entered in the previous year, our organization naturally expanded upon our commitment to serving our stakeholders with integrity and to upholding the environmental, social, and governance standards and aspirations we have documented over the years.

As First Interstate has grown, so has our responsibility to the many places we call home. At our very core, we remain a community bank and place the well-being of our communities at center. Our franchise development has not changed what is integral to our being - our Mission, Vision, and Values - and has rather highlighted the necessity of nurturing those differentiating factors to sustain our place in the community and the banking industry. We attribute our long-term strength and stability to these guiding principles, and we continue to look to them as we shape our actions and consider our impacts going forward.

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LETTER TO STAKEHOLDERS

To Our Stakeholders:

Change and challenge are constant companions, and the way forward is to meet them with a clear understanding of one's own principles and aspirations. Since 1968, First Interstate Bank has grown from a single branch in Wyoming to more than 300 banking offices across 14 states, all while navigating shifts in the world around us - economic, political, social, environmental, and more. We've done so by focusing our energy on what is well within our power

to control.

We may not be able to control the world around us, but we can control how we choose to operate, which values we uphold, and who we are beholden to. As a community bank, First Interstate is deeply invested in the places where we live, work, and play. Our focus has always been and will remain on serving all our stakeholders - employees, clients, communities, and shareholders - to the best of our abilities. One of our core values remains People First, Always, and from it flow our other guiding principles: Seek Greatness, Integrity, Celebrate Success, and Commitment to Community.

In 2023, the First Interstate Bank franchise entered the year transformed by an earlier merger. While significantly expanding a footprint might challenge other organizations to maintain their stakeholder commitments, I am proud to say our efforts in that regard were not diluted and were instead strengthened. We entered new markets by demonstrating our intent to take care of the people within, such as providing new employees with compelling compensation, benefits, and advancement opportunities; generating opportunities to donate time and resources to local nonprofits in need; and identifying places that could benefit from increased investment in community development.

As First Interstate has grown, so has our responsibility to the places in which we operate, and we seek to be a source of strength and stability throughout our footprint.

In early 2023, as high-profile banks failed and the industry was threatened with a crisis of confidence, First Interstate held firm and weathered the storm. By adhering to our long-held principle of prudent risk management and our focus on making decisions based on long-term impacts, we maintained a strong balance sheet and protected shareholder value.

Our steadiness in times of uncertainty, and in all economic climates, has served us and our markets well. As our franchise has expanded over the years, so have our resources and influence. In the following pages, we present our investments in environmental, social, and governance issues and initiatives, and we share the meaningful impacts on our stakeholders. We recognize there is always room for improvement, but with our Mission, Vision, and Values as guides, we are confident we are on the right path.

Sincerely,

Kevin P. Riley

President & CEO

First Interstate BancSystem, Inc.

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Executive Summary

2023 By the Numbers

Our Formidable Footprint

First Interstate Bank operates more than 300 banking offices across 14 states.

We employed more than

3,500

employees as of December 31, 2023

Our Times Square Moment

For Community Banking Month in May, Nasdaq spotlighted First Interstate Bank on its tower in New York City's Times Square.

Coinciding with our

55th

anniversary

the recognition lauded our commitment

to clients and communities.

E-cycling

Drives

The Billings and Eastern Montana market held three events to collect retired electronics, keeping these materials out of local landfills.

MONTH	COLLECTION
	WEIGHT IN LBS.
March	1,881
April	1,157
November	4,284
TOTAL	7,322

Financial Education

From children to seniors, anyone can benefit from financial literacy. Our bankers are dedicated to providing practical financial education to help people make important decisions.

Bankers hosted 523 financial education presentations, drawing 10,865attendees

and

distributing over 6,300 information packets

An App That Delivers

First Interstate's mobile app remains highly rated in both the Apple App Store and the Google Play Store. The app has earned a rating of 4.7 out of 5 stars in the Apple App Store from more than 17,400 reviewers.

Energy

Conservation

The 2023 LED conversion and upgrade projects created

60,830kWh

annual reduction in energy consumption.

Student Loan Support

First Interstate offers a Student Loan

Debt Repayment Program to qualified employees to help pay off student loans and alleviate a financial burden.

First Interstate contributes

$100per month to qualified employees totaling

$325,600

in 2023 for 447 employees

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Director Independence

14of 15-member

ourBoard of Directors,

including the Chair of the Board,

are independent under Nasdaq rules.

Balanced Workforce

Throughout First Interstate, gender balance is maintained at nearly all levels. Our overall workforce comprises:

68.2% identify as female

31.6% identify as male

Giving Back in a Big Way

Over the past 34 years, the

First Interstate BancSystem

Foundation, together with the

Bank, has invested more than

$87M

in philanthropic funds in our communities.

Established in 2022, the employee-driven

Believe in Local campaign has provided

$2Min total support to our communities.

Total volunteer hours:

46,781

Total organizations served:

1,536

Board service hours:

10,322

0.2% non-binary/ undisclosed

Our Executive Team consists of six female and two male leaders.

Community Reinvestment Act (CRA)

First Interstate received an Outstanding CRA rating on our most recent exam cycle for serving low- and moderate-income(LMI) communities.

9 of our 10 CRA

lastratings

have been Outstanding

During the summer of 2023, $1 million was awarded across our footprint to

40 impactful nonprofit organizations

each $25Kgrant to

receiving afurther their mission.

Time, Talent, Treasure

In 2023, First Interstate and the First

Interstate BancSystem Foundation remained intent on showing up and giving back in whatever form makes the greatest impact.

Annual

Volunteer

Day

One day each year, First Interstate closes our doors for Volunteer Day, sending staff into the community to support local nonprofits with their time and talent. On September 13, staff fanned out in all 14 states to make a difference.

12K+hours

3,150+volunteers Nearly410 organizations

assisted

Partnerships

Through the Federal Home Loan Bank Des Moines' Member Impact Fund, First Interstate's commitment to community garnered

36nonprofit organizations in Wyoming

Idaho

and $613,500

in philanthropic support

to further their missions.

Total Company donations and	105 projects helping seniors
Foundation grants awarded:
	161	projects helping youth
NEARLY	49	affordable housing projects
$9.3M	118	projects addressing hunger
Total employee matching:	28	financial education or
OVER$884K		skill-based volunteering
89	homelessness projects

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2024 Corporate Responsibility Report

SOCIAL REPORT

People and community remain the heart and soul of our franchise.

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SOCIAL REPORT

People and community remain the heart and soul of our franchise.

First Interstate's market may span 14 states, but, at our core, we remain a local community bank. Our strength, stability, and longevity are a testament to the people that support us and the people we are honored to support around us.

We cannot succeed without the dedication of our valued employees, the trust of our loyal clients, or the respect of our gracious neighbors and communities. These people all show up for us, and that's why First Interstate continues to show up for them - and in a big way.

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SOCIAL REPORT  EMPLOYEES

Taking Care of Employees

At times, it seems that life simply throws one curveball after another. In 2023, pandemic fears eased, only to be replaced by inflationary concerns and worse - stress in the financial services industry. Early 2023 saw the failure of a few regional banks, spurring a crisis in confidence for the industry. First Interstate, however, held fast and emerged from a tumultuous period

in a sound position thanks to a strong balance sheet and prudent risk management. While other banks grappled with operational issues in the fallout, First Interstate remained stable with few concerns, providing our markets and the employees serving those markets with reassurance in uncertain times.

No matter the climate around us, First Interstate strives to be an employer of choice across all 14 states in which we operate and provide a positive, stable environment for our workforce. We recognize our value chain begins and ends with our employees, and we work hard to provide benefits and attractive overall compensation to train, maintain, and retain top talent. As of December 31, 2023, that talented workforce numbered 3,585 full-time equivalent employees. Our employee count at year-end represents a decrease of 198 employees from December 31, 2022, which can be attributed, in part, to a workforce reduction enacted in the fourth quarter of 2023 to manage the performance of our Company to compete effectively in the current banking environment.

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