The Japan-based firm won regulatory approval for the sale, likely to be among the biggest IPOs this year, with the dual listing expected to raise as much as 113 billion yen ($1.05 billion), including an option to sell more shares if demand is strong.
The deal would value Line at about $5.5 billion, and was described by Bloomberg as this year's biggest tech offering globally.
Line, which is owned by South Korean Internet provider Naver Corp., said it expected to list its shares on July 14 in New York and July 15 in Tokyo.
It will offer 13 million new shares in Japan, with another 22 million in the U.S., according to documents filed with the Tokyo Stock Exchange.
The indicative share price would be 2,800 yen apiece.
"(The company) has made the decision to go public in both Japan and the United States to further enhance its strong position in Asia and to continue a more active global expansion," the company said.
The sale comes two years after Line initially announced plans to list in an IPO that was later shelved.
The July offering would be the biggest in Tokyo since Japan Post made its long-awaited trading debut in November with a share sale that topped $11.5 billion.
The popular app lets users make free calls, send instant messages, and post photos or short videos, along with a host of other paid-services. It combines attributes from Facebook, Skype and WhatsApp.
Line's messaging service launched in 2011 after the quake-tsunami tragedy damaged Japan's telecoms infrastructure nationwide forcing people to use to online resources to communicate.
It is best known for letting users send each other cute cartoon "stickers", and is hugely popular in Japan, particularly among teenagers.
The app, which claims to have more than 200 million monthly active users, has a strong presence in Asian markets such as Thailand, Taiwan and Indonesia, as well as some Spanish-speaking areas, including Spain and Mexico.
But the company has been looking to expand in bigger markets, such as the U.S..
Proceeds of the share sale would be earmarked for investing in its message app and financing its growth strategy at home and overseas, Line said.
"We will continue mergers and acquisitions and other investment globally, but there is nothing decided at this point" in terms of a particular deal, the company said.
Last year, Line posted revenue of 120 billion yen, up 40 percent from the year before, but a small overall loss, which it blamed on rising staff costs and other expenses.
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