National newspaper the Yomiuri Shimbun said the agency's statistics show there were 1,297 cases of transfer fraud last month, down 38 per cent from peak levels recorded in March and June 2008.
Transfer fraudsters attempt to dupe bank customers into moving money via automated ATM machines into accounts supposedly belonging to relatives or friends in need or urgent cash.
Japan Today notes that people behind the schemes usually target the elderly.
However, according to the police agency's numbers, the amount of money moved by victims of the scams has declined by nearly half - 46 per cent - to 157 billion yen ($1.61 billion) since its campaign began.
Nevertheless, the latest figures fall short of the NPA's target of reducing bank transfer fraud by half, the newspaper noted.
The NPA campaign saw it mobilise 58,000 officers to warn bank customers about transfer scams at 81,000 ATM locations - or around 83 per cent of Japan's cash machines.