The figure was less than the 3.6 trillion yen estimates by Tokyo money market brokers for Japan's first dollar-selling, yen-buying intervention in 24 years to stem the currency's weakening.
Total spending on currency intervention from August 30 to Sept 28 is widely believed to have been used entirely for the Sept 22 intervention, according to the ministry's figures. It would surpass the previous record for dollar-selling, yen-buying intervention in 1998, which was 2.62 trillion yen. The dates for spending will be announced in November.
This was a big burst of intervention, if it had happened on a single day, underscoring Japanese authorities' determination to defend the yen, said Daisaku Ueno, chief forex strategist at Mitsubishi UFJ Morgan Stanley Securities.
As Japan continues to intervene solo, the impact of further intervention will diminish, he said.
The intervention, which took place after the yen slumped to a 24 year low of nearly 146 to the dollar, triggered a sharp bounce of more than 5 yen per dollar from that low, although the currency has since fallen to around 144.25.
The recent sharply one-sided yen declines makes it hard for companies to set business plans. It's undesirable and bad for the economy, said Haruhiko Kuroda, Bank of Japan's governor, at a meeting with cabinet ministers on Friday.
Japan held around $1.3 trillion in reserves, the second biggest after China, of which $135.5 billion was held as deposits were parked with foreign central banks and the Bank for International Settlements, according to foreign reserves data released on Sept 7. The deposits can be tapped to finance further dollar-selling, yen-buying intervention.
Even if it were to intervene, Japan probably won't have to sell US Treasury bills and tap this deposit for the time being, said Izuru Kato, chief economist at Totan Research, a think-tank arm of a major money market brokerage firm in Tokyo.
Japan would need to dip into its holdings of around $1.04 trillion if the deposits dry up.
The most liquid types of foreign assets that Japan holds are the ones that can be converted into cash immediately.
ALSO READ: Japan has a record trade deficit in August as energy imports soar.
Other holdings include gold, reserves at the International Monetary Fund and IMF special drawing rights, although procuring dollar funds from these assets would take time, analysts say.