When most people think about programming, they picture sleek modern languages like Python, JavaScript, or Java. What they don’t picture is COBOL, a language first designed in the late 1950s. Yet, this “ancient” language continues to quietly power the systems we all depend on daily.

From swiping your credit card to withdrawing cash at an ATM to processing your payroll, there’s a good chance COBOL is working behind the scenes. It is unequivocally one of the most important invisible engines of the global economy.

The Scale of COBOL’s Footprint

The persistence of COBOL is a reflection of how deeply it’s embedded in critical infrastructure.

• Experts estimate there are between 200 and 800 billion lines of COBOL code still in active use worldwide.
• 70–80% of global business transactions run on COBOL-powered systems.
• 95% of ATM transactions still pass through COBOL programs.
• 92 of the top 100 banks continue to rely on IBM mainframes running COBOL.
• In the U.S., up to 80% of the federal IT budget goes toward maintaining these legacy systems.

This staggering footprint makes COBOL one of the most enduring technologies in history. Replacing it entirely would be like trying to rebuild the foundation of a skyscraper while people still live inside.

Why COBOL Refuses to Die

So why hasn’t COBOL been replaced after six decades? Three reasons stand out:

1. Proven Reliability: COBOL systems are designed for high-volume, mission-critical transactions. Banks, insurance companies, and governments trust them because they’ve been battle-tested for decades. Few modern systems can match their uptime and accuracy.
2. Deep Integration: COBOL systems are at the core of how money, benefits, and data flow globally. Replacing them isn’t as simple as swapping one program for another.
3. High Risk of Failure: Even small errors in core financial or government systems can have devastating effects. That’s why many CIOs take the stance: “If it isn’t broken, don’t fix it.”

The Growing Challenges

Despite its strengths, COBOL’s dominance creates challenges:

• Talent shortage: The average COBOL programmer is about 55 years old, with many nearing retirement. Few new developers are learning the language.
• High maintenance costs: Some organizations spend up to 75% of their IT budgets just keeping these systems alive.
• Security risks: Legacy systems weren’t built for today’s cybersecurity threats, making them harder to protect.

This combination of risks and costs means organizations can’t ignore modernization forever.

The Road Ahead

COBOL’s story isn’t just about the past—it’s about the future. While full replacement may be unrealistic, AI-assisted modernization offers a bridge between old and new. Emerging tools can:

• Analyze and document undocumented COBOL code.
• Translate business logic into modern languages like Java or Python.
• Generate automated tests to ensure critical functionality isn’t lost.

In other words, AI may finally make modernization feasible without the massive risks that have stalled it for decades.

Conclusion

COBOL is the hidden backbone of modern society. For now, it continues to run the world quietly, reliably, and at scale. But as the workforce ages and costs mount, the question is no longer whether modernization will happen, but how.

In the next part of this series, we’ll explore the hidden costs of sticking with COBOL and why organizations can’t afford to simply maintain the status quo.