The Tax Office will force cryptocurrency exchanges to hand over up to 1.2 million traders’ transaction details each year as it cracks down on people dodging their capital gains liabilities, amid a growing mania for the digital tokens as an alternative store of wealth among younger generations in particular.

As part of a surveillance effort announced in April, the ATO said its latest data collection protocol would require designated cryptocurrency exchanges to provide the names, addresses, birthdays and transaction details of traders to help it audit compliance with obligations to pay capital gains tax on sales.