PSN Parsons Corporation

Parsons Corporation (NYSE: PSN) announced today that it has been recognized by Ethisphere, a global leader in defining and advancing the standards of ethical business practices, as one of the 2025 World’s Most Ethical Companies. This marks the sixteenth consecutive year that Parsons has been honored with this recognition.

In 2025, 136 honorees were recognized spanning 19 countries and 44 industries. The company is one of only three honorees in the Engineering Services category.

“Being named one of the World’s Most Ethical Companies for 16 consecutive years exemplifies the value we place on ethics, integrity, and core values in driving our culture of performance,” said Carey Smith, chair, president, and chief executive officer of Parsons. “The principles that mark this distinction are integral to how we have operated during our 81-year history. These values will continue to serve as the foundation of our growth in the national security and critical infrastructure sectors as we deliver for our customers, employees, and shareholders.”

The heart of Parsons’ ethics program is employee engagement combined with transparency set forth at the executive and management leadership levels which serves as the ethos of the company’s business. Parsons long-standing commitment to integrity also sets the standard and expectation for suppliers and vendors.

“Our employees’ commitment to core values and integrity is the primary reason that we have been recognized consistently by Ethisphere,” said Mike Kolloway, chief legal officer of Parsons. “Our global community continues to enhance our ethics program, allowing us to serve our customers’ missions with the highest level of ethical business practices.”

Read more about how Parsons' core value of integrity informs the company’s business practices at https://www.parsons.com/care/governance/.

Methodology & ScoringThe World's Most Ethical Companies assessment is grounded in Ethisphere's proprietary Ethics Quotient®, which requires companies to provide 240+ different proof points on practices that support robust ethics and compliance; governance; a culture of ethics; environmental and social impact; and initiatives that support a strong value chain. That data undergoes further qualitative analysis by their panel of experts who spend thousands of hours vetting and evaluating each year's group of applicants. This process serves as an operating framework to capture and codify best-in-class ethics and compliance practices from organizations across industries and from around the world.

Honorees To view the full list of this year’s honorees, please visit the World’s Most Ethical Companies website, at https://worldsmostethicalcompanies.com/honorees.

About ParsonsParsons (NYSE: PSN) is a leading disruptive technology provider in the national security and global infrastructure markets, with capabilities across cyber and intelligence, space and missile defense, transportation, environmental remediation, urban development, and critical infrastructure protection. Please visit Parsons.com and follow us on LinkedIn and Facebook to learn how we're making an impact.

About EthisphereEthisphere is the global leader in defining and advancing the standards of ethical business practices that strengthen corporate brands, build trust in the marketplace, and deliver business success. Companies turn ethics, compliance, and culture into a business advantage by leveraging Ethisphere’s data-driven program and culture assessments featuring the latest guidance and the practices of hundreds of global organizations across the 8 pillars of an ethical culture, and 240+ ethics, compliance, social, and governance data points delivered through a proprietary software platform. Ethisphere also honors superior integrity programs through World’s Most Ethical Companies® recognition, brings together a community of industry experts with the Business Ethics Leadership Alliance (BELA), and advances ethical business practices through the Global Ethics Summit, Ethisphere Magazine and the Ethicast podcast. For more information, visit https://ethisphere.com.

Media Contact:Bryce McDevitt+1 703.851.4425Bryce.McDevitt@Parsons.com

Investor Relations Contact:Dave Spille+ 1 703.775.6191Dave.Spille@Parsons.us