Top 10 Richest Men In Ireland According To Forbes (2025)

Ireland is often celebrated for its rich history, lush landscapes, and cultural exports like literature and music. But in recent years, the Emerald Isle has also been making headlines for something a bit shinier—its billionaires. Despite having a relatively small population of just over 5 million, Ireland boasts an impressive roster of ultra-wealthy individuals who have made fortunes in everything from cutting-edge tech to old-fashioned industry.

According to the latest Forbes list for 2025, here are the top 10 richest men in Ireland, their net worth, industries, and how they climbed to the very top of the financial ladder.

1. John Collison – $10.1 Billion

Age: 34
Source of Wealth: Payment software (Stripe)
Industry: Technology

At just 34, John Collison is not only Ireland’s richest man but also one of the youngest billionaires in the world. Along with his brother Patrick, he co-founded Stripe, a global payments processing company now valued at over $50 billion.

Born in Limerick and educated at Harvard, John dropped out to scale Stripe after realizing the huge gap in smooth online payment systems for businesses. Today, Stripe powers payment solutions for millions of companies globally, from startups to Fortune 500 giants.

John’s fortune has been fueled by Stripe’s meteoric rise, investment rounds from major funds, and its continued dominance in the fintech space. Despite immense wealth, he’s known for keeping a relatively low profile and focusing on product innovation.

2. Patrick Collison – $10.1 Billion

Age: 36
Source of Wealth: Payment software (Stripe)
Industry: Technology

Patrick Collison, John’s elder brother, shares not only the same fortune but also the same entrepreneurial journey. As CEO of Stripe, Patrick is the visionary driving the company’s long-term strategy, expansion into new markets, and adoption of emerging technologies like cryptocurrency payments.

Before Stripe, Patrick was already a prodigy—he won the Young Scientist of the Year award in Ireland at just 16 and later sold his first startup, Auctomatic, for millions. His leadership has made Stripe a household name in fintech and a key player in shaping how money moves online.

Together, the Collison brothers symbolize Ireland’s emergence as a tech hub and are inspiring a new generation of Irish entrepreneurs.

3. Shapoor Mistry – $8 Billion

Age: 60
Source of Wealth: Diversified (Shapoorji Pallonji Group)
Industry: Diversified

Shapoor Mistry heads the Shapoorji Pallonji Group, a global conglomerate with interests in engineering, construction, real estate, and infrastructure. Though the business empire originated in India, Shapoor holds Irish citizenship and has expanded operations internationally, making him a central figure in Ireland’s billionaire ranks.

Under his leadership, the group has handled massive projects in over 60 countries, from luxury hotels to industrial facilities. Mistry’s wealth comes from both direct business operations and a significant stake in Tata Sons, the holding company of the Tata Group—one of the largest corporate groups in the world.

4. John Grayken – $7.3 Billion

Age: 68
Source of Wealth: Private equity (Lone Star Funds)
Industry: Finance & Investments

American-born but now an Irish citizen, John Grayken is the founder of Lone Star Funds, a private equity firm specializing in distressed assets. His fortune has been built on acquiring undervalued real estate, corporate debt, and financial institutions, often during economic downturns.

Grayken’s success lies in his ability to spot opportunities where others see crisis—turning struggling businesses and properties into profitable ventures. While based in Dublin, his investment reach is global, spanning the Americas, Europe, and Asia.

5. Firoz Mistry – $4 Billion

Age: 28
Source of Wealth: Diversified (Shapoorji Pallonji Group)
Industry: Diversified

At just 28, Firoz Mistry is one of Ireland’s youngest billionaires. He is part of the Mistry family that controls the Shapoorji Pallonji Group, inheriting not only a stake in the vast conglomerate but also a legacy of large-scale construction and industrial projects.

While much of his wealth comes from family holdings, Firoz is also actively involved in modernizing and expanding the group’s portfolio, particularly in renewable energy and sustainable infrastructure.

6. Zahan Mistry – $4 Billion

Age: 26
Source of Wealth: Diversified (Shapoorji Pallonji Group)
Industry: Diversified

Zahan Mistry, Firoz’s brother, shares the same net worth and family business legacy. Though only in his mid-20s, Zahan represents the next generation of Mistry leadership and has shown interest in steering parts of the conglomerate toward new technologies and global markets.

Together, the Mistry brothers are likely to play a crucial role in the long-term evolution of the Shapoorji Pallonji empire, with a focus on diversification beyond construction.

7. John Dorrance III – $3.2 Billion

Age: 81
Source of Wealth: Campbell Soup
Industry: Food & Beverage

John Dorrance III is the heir to the Campbell Soup fortune. Though American-born, he chose Ireland as his home and tax residence decades ago. His wealth comes primarily from his inherited stake in Campbell Soup Company, a household name in packaged foods.

Dorrance has kept a relatively quiet profile compared to tech billionaires, focusing on philanthropy and investments. He’s a reminder that much of Ireland’s billionaire wealth isn’t solely generated within the country but also attracted from abroad due to its favorable business climate.

8. Denis O’Brien – $3 Billion

Age: 66
Source of Wealth: Telecom (Digicel)
Industry: Telecom

Denis O’Brien is one of Ireland’s most famous—and sometimes controversial—billionaires. He founded Digicel, a telecom giant operating across the Caribbean, Central America, and the Pacific. O’Brien made his fortune by expanding into underserved mobile markets, offering affordable telecom services.

Beyond telecom, he has diversified into media, hospitality, and energy. While Digicel has faced financial restructuring in recent years, O’Brien’s personal wealth remains substantial, and he continues to be a major figure in Irish business circles.

9. Eugene Murtagh – $2.7 Billion

Age: 82
Source of Wealth: Building materials (Kingspan)
Industry: Manufacturing

Eugene Murtagh founded Kingspan Group in 1965, turning it into a global leader in high-performance insulation and building materials. The company is now a major player in sustainable construction, with operations in over 70 countries.

Murtagh’s wealth comes from decades of steady growth, international expansion, and an increasing demand for energy-efficient building solutions. Even after stepping down from active management, he remains a significant shareholder.

10. Dermot Desmond – $2.2 Billion

Age: 74
Source of Wealth: Finance & Investments
Industry: Finance & Investments

Dermot Desmond is a self-made billionaire with a diverse investment portfolio. He made his initial fortune by founding the International Investment & Underwriting firm and selling his stockbroking business to Ulster Bank in the 1980s.

Desmond has since invested in sectors ranging from golf courses (including Scotland’s Gleneagles Hotel) to sports teams and financial services. Known for his strategic thinking, he’s regarded as one of Ireland’s shrewdest investors.

Final Thoughts

Ireland’s billionaires are a diverse bunch—tech innovators, industrial giants, heirs to global fortunes, and investment gurus. While the Collison brothers symbolize the country’s future in technology, figures like Eugene Murtagh and Denis O’Brien represent the more traditional, brick-and-mortar approach to wealth creation.

Interestingly, Ireland’s billionaire list also reflects its global connections. Many of these fortunes have roots abroad, from American soup to Indian conglomerates, yet Ireland’s welcoming business environment and international tax positioning have made it a home for significant wealth.

In the years ahead, expect Ireland’s tech scene to produce even more homegrown billionaires, while established players in manufacturing, finance, and diversified sectors continue to grow their fortunes.