In the midst of a major push to build its advertising business, Twitter plans to raise as much as $1.5 billion by tapping the debt markets for the first time.
The San Francisco short-messaging company is selling convertible bonds in two $650 million chunks to institutional investors, according to a regulatory filing on Wednesday.
Buyers can purchase an additional $100 million on each. Twitter said it would use the cash for "general corporate purposes."
Twitter shares fell more than 1% in after-hours trading following news of the debt sale.
Twitter which went public last November is not yet profitable.
It secured a $1 billion credit line ahead of the IPO that raised about $2 billion for the company.
Anthony Noto, a former Goldman Sachs banker who helped guide the IPO, replaced Mike Gupta as chief financial officer in July.
Twitter shares got a boost in regular trading on Wednesday after UBS lifted its rating to "buy" from "neutral" on expectations of advertising revenues climbing.
The launch of promoted videos and a "buy now" feature could position Twitter to take advantage of key growth areas in digital advertising, UBS said.
"Our advertising checks indicate Twitter is seeing positive momentum," Eric Sheridan, an analyst with UBS, wrote in a research report.