IBM Shares Plunge After Quarterly Earnings Miss as Executives Insist AI Won't Kill the Mainframe

IBM’s latest quarterly report delivered a sharp disappointment to investors, even though the company remained profitable. The technology group posted revenue of $17.2 billion for the quarter and net income of $2.2 billion, but those figures still fell well short of Wall Street’s expectations. The market reaction was swift: IBM shares plunged 25% in a single day, and executives also lowered the company’s full-year growth outlook.

The biggest source of weakness came from IBM’s infrastructure segment, long supported by its mainframe business. That division suffered a steep 42% year-over-year decline, making it the primary reason the company’s overall performance missed forecasts. For a company whose enterprise reputation has been built in part on large-scale computing systems, the drop raised immediate concerns about both timing and demand.

The decline in mainframe sales did not only hurt hardware revenue. It also created pressure elsewhere in IBM’s business. Because mainframe customers often purchase high-margin software alongside the systems themselves, weaker hardware sales also translated into softer software income, amplifying the impact on results.

Rising AI-related costs are reshaping customer spending

According to CEO Arvind Krishna, the current artificial intelligence boom is changing purchasing behavior across enterprise IT. He said the cost of data centers and computer components has climbed between 15% and 30% as AI demand accelerates. That increase is forcing customers to reassess budgets and, in many cases, delay large infrastructure purchases such as mainframes.

In other words, IBM’s problem may be tied less to disappearing interest and more to the financial pressure created by a rapidly changing technology environment. As companies spend more to support AI ambitions, they appear to be postponing some traditional system upgrades rather than abandoning them altogether.

IBM says this is a pause, not the end of the mainframe

Despite investor anxiety that AI could reduce the relevance of legacy enterprise systems, IBM’s leadership pushed back against that interpretation. Executives argued that demand for mainframes has not vanished. Instead, they described the current slowdown as a temporary shift in buying cycles, with customers delaying orders rather than walking away from the platform.

That distinction is critical for IBM. If management is right, the recent weakness reflects timing and budget pressure, meaning purchasing activity could return once customers regain flexibility. If not, the decline could point to a deeper structural challenge as AI spending competes more directly with traditional infrastructure investments.

For now, IBM is trying to reassure the market that its core enterprise systems still matter, even as AI reshapes technology budgets. But after a quarter marked by a major earnings miss, a sharp infrastructure decline, and a steep sell-off in the stock, investors appear unconvinced and will be watching closely to see whether deferred mainframe demand eventually comes back.