FIRSTENERGY CORP

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

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Letter toOur Shareholders

April 1, 2026

Dear Fellow Shareholders,

Thank you for your investment and trust in FirstEnergy.

Over the last three years, we have made FirstEnergy into a stronger and more agile company focused on delivering a positive customer experience and sustainable long-term value. Our performance in 2025 reflects the impact of this work. We executed well, improved service reliability, advanced our regulatory strategy, and delivered strong financial results. We demonstrated the power of our business model and built a solid foundation for continued growth.

I value the close partnership with our Board and leadership team as we continue executing our strategy with a steadfast commitment to good governance.

Delivering results

In 2025 we advanced our cultural, structural and leadership transformation. We moved decision-making closer to our customers by decentralizing operational, financial and regulatory functions and strengthening accountability. With this alignment, we achieved constructive regulatory outcomes that support needed investments in service reliability.

We delivered on each of our key financial targets, including Core Earnings (non-GAAP) per share, base O&M, capital investments and cash from operations. In December, S&P upgraded our credit ratings, reflecting our stronger financial profile and the progress we have made moving beyond legacy matters.

We deployed $5.6 billion in capital through our Energize365 program in 2025 to enhance reliability, resiliency and system capacity. These investments are driving measurable benefits, including a 10% improvement in systemwide distribution reliability compared to 2024.

Our 2025 performance shows our strategy is working. We have a clear roadmap to build on this success. In early 2026, we expanded our Energize365 program to $36 billion for 2026-2030, a 30% increase over our prior five-year plan. This reflects our financial strength and our responsibility to meet customer expectations for reliability and grid resiliency, while offering a compelling, low-risk value proposition to investors.

Building for the future

Our meaningful growth opportunities extend well beyond our current plan. Data center development, advanced manufacturing and electrification are reshaping demand patterns, while rising customer expectations require a more modern, resilient system. These needs align with our assets, location and business model.

In February we filed for approval of a fully regulated, 1.2 gigawatt combined‑cycle natural gas facility in Maidsville, West Virginia. This project represents a significant opportunity to keep power reliable and affordable for our West Virginia customers and support the state’s broader energy objectives.

2026 PROXY STATEMENT

Letter toOur Shareholders

We also expect substantial long-term transmission investment. Across our footprint, nearly 70% of our lines and 30% of our substation assets will approach end‑of‑life over the next decade. We plan to pursue additional opportunities through PJM’s competitive Open Window process to support the region’s growing transmission needs. With our extensive, well-situated transmission network, FirstEnergy will continue to play a critical role as an engine of economic development keeping affordability and reliability at the center of our work.

Enhancing our performance culture

Our progress is driven by our employees. In 2025 we advanced a more efficient and sustainable operating model to empower our teams and elevate our performance culture. We also brought 2,500 employees back to the office to support greater collaboration and engagement. These actions reinforce our focus on continuous improvement and execution.

Ethical conduct is foundational to how we operate and make decisions. We were proud to earn recognition for governance and transparency through the CPA‑Zicklin Trendsetter designation and Ethisphere Compliance Leader verification. We remain committed to maintaining the highest standards of ethics, integrity and compliance.

Creating shareholder value

Our clear strategy and disciplined execution are delivering results. In 2025 we generated total shareholder returns (TSR), including dividends, of 17.3%. This compares to average TSR of 15.5% for our regulated peers in the S&P 500 Utility Index.

We remain focused on building our momentum and driving strong, reliable performance. With continued Board approval, we expect to declare dividends totaling $1.86 per share in 2026. This represents a 4.5% increase from 2025 and aligns with our target payout ratio.

Looking ahead

I appreciate the commitment of our employees, leadership and Board as we continue transforming FirstEnergy into a premier electric company. I also want to thank Melvin Williams for his five years of service on our Board. His perspective and leadership strengthened our company and supported our progress.

Our organization is aligned around our mission to deliver safe, reliable and affordable service to the 6 million customers who depend on us while creating long‑term value for you, our shareholders. I am proud of what we’ve achieved and confident in our future.

We look forward to continuing our dialogue with you at the 2026 Annual Meeting and throughout the year.

Thank you for your continued support of our company.

Brian X. Tierney

Board Chair, President and Chief Executive Officer

FIRSTENERGY CORP.

Notice ofAnnual Meetingof Shareholders