By market open, shares had taken off 15.1% to $33.29.
The company, which makes electrical meters for the energy sector, posted fourth-quarter net income of 36 cents a share. Revenue of $524 million came in flat on the year-ago quarter.
Analysts surveyed by Thomson Reuters had anticipated net income of 74 cents a share on $526.94 million in sales.
Over fiscal 2013, the Washington-based company recorded per-share earnings of $1.90, lower than an expected $2.29 a share due to a discrete tax item which had a 35 cent impact.
"While fourth quarter results were impacted by a goodwill impairment charge in our Electricity segment and a discrete tax charge, the steps we have taken in 2013 position Itron to be more competitive in a tough economy and global marketplace," said CEO Philip Mezey in a statement.
For full-year 2014, management expects earnings between $1.30 and $1.80 a share with sales of $1.825 million to $1.925 billion. Analysts had predicted earnings of $2.04 a share on $1.91 billion in revenue.
"Despite a more conservative outlook, I am encouraged by the progress of our ongoing efforts to improve financial performance and build a solid foundation for future growth and profitability," added Mezey.
Following earnings, JPMorgan downgraded the stock to "underweight" from "neutral", while Brean Capital cut it to "sell" from "hold" with a $28 price target. Both analyst firms cited lower-than-expected guidance as reason for the ratings revision.