Coin production surged 20% in fiscal 2013 ended Sept 30 thanks largely to burgeoning border trade and the rising number of vending machines, says the Treasury Department.
Director-general Naris Chaiyasoot said the number of vending machines has increased substantially, particularly in the North, he said, adding there are as many as 70 vending machine operators in Udon Thani province.
At present, 20 billion coins with a combined value of 42 billion baht are in circulation.
Thailand's border trade has soared in recent years ahead of market integration under the Asean Economic Community in late 2015. The opening up of Myanmar's economy is another growth driver.
The Commerce Ministry data showed Thailand's border trade with Malaysia, Myanmar, Laos and Cambodia rose by 0.46% over the same period to 457 billion baht in the first half. Thailand and Malaysia trade, valued at 247 billion baht, accounted for 54.2% of the total, followed by Myanmar (95.3 billion), Laos (67.3 billion) and Cambodia (46.9 billion).
Mr Naris said the Treasury Department needs to increase coin production every year as people always keep a number of coins at home and a portion is left idly in donation boxes.
It typically takes time before coins in donation boxes are back into circulation, he explained.
To save coin production costs, the department may in the future hire private companies to purchase donated coins, mainly from temples, and put them back into circulation. Some denominations carry higher production costs than their face value, he said.
The department plans to sign a cooperation agreement with the United Kingdom's Royal Mint to set up in Thailand an Asean training centre for coins.