The Bank said there were shops in Tongatapu and the outer islands offering unlicensed foreign exchange services, including cash conversion.
Only dealers authorized by the Reserve Bank are allowed to move money in and out of Tonga.
“Providing foreign exchange services without the required license is an offence,” the Bank said.
Illegal dealers have been warned to immediately stop what they were doing.
The Reserve Bank warns that Individuals face three years in prison and fines of up to TP$20,000.