Sony shares plunged 12 percent at the open in Tokyo on Thursday after the electronics giant warned it would lose $2.14 billion this fiscal year, more than four times its earlier forecast.
The shares fell to 1,865.5 yen ($17) in the first few minutes of frenzied trading in response to Sony's announcement, which came after Japanese markets had closed Wednesday.
The company blamed the ballooning loss estimate on struggles at its mobile phone business, where it said it would cut staff by 15 percent, or about 1,000 jobs. Demand for its smartphones has come under increasing pressure from rivals including Samsung and Apple.
Sony also said it would not pay dividends for the first time since its shares started trading in Tokyo in 1958.
The surprise news that Sony was heading for a 230 billion yen ($2.14 billion) net loss in the fiscal year to March 2015 comes only months after it tipped a shortfall of just 50 billion yen, citing a turnaround in its television unit.
The announcement was likely to resurrect fears that what used to be the world's leading electronics company has a lot more work ahead to cast off years of losses.
Sony has seen its credit rating slashed to junk as it undergoes an overhaul, including exiting the PC business and liquidating assets that saw the $1.0 billion sale of its Manhattan headquarters.