The number of digital subscriber lines for high-speed Internet access reached 400,760 at the end of July, the telecommunications ministry said in a report Thursday.
The figure constituted a jump of more than 100,000 from the previous month and posted a 250-fold increase from a year earlier, the ministry said.
This surge reflects price competition among providers and a shorter waiting period for the installation of connections, according to the Ministry of Public Management, Home Affairs, Posts and Telecommunications.
The popularity of broadband connections, which also include asymmetrical digital subscriber line services, is growing in Japan.
Major ADSL connection providers have recently announced that rate cuts of between 30 percent and 50 percent will be introduced in mid-August.