The number of online trading accounts opened by individual investors in Japan is expected to top 2.2 million by the end of this year, up markedly from around 320,000 in October 1999, according to data released Thursday.

There were some 780,000 Internet accounts as of the end of March. The data, released by Daiwa Institute of Research and other economic research institutes, indicate about 10 percent of individual investors have online trading accounts.

The institutes attributed the sharp rise in Internet-based stock trading to steep cuts in commissions collected by securities houses on online trades, following the liberalization of such commissions last October.

ORIX Securities Inc., for example, lowered its minimum commission from 1,800 yen to 1,400 yen, effective March 1, in a bid to lure more individuals to online trading.

Among securities companies specializing in online trading, E*Trade Securities Co. earned about 10,000 new accounts within a month of cutting commissions this spring.

But major securities companies are staying out of the commission-cutting competition, saying companies conducting online trades for between 1,000 yen and 2,000 yen will be unable to stay in business.

Shuichi Numaguchi, president of Nikko Beans Inc., an affiliate of Nikko Securities Co., says larger brokerages can attract customers to online trading despite charging higher commissions because their computer systems are more reliable and they offer better investment information.