Unofficial Forex Trade Taxable

The Iranian National Tax Administration (INTA) said foreign currency dealers must also pay tax if they trade outside the purview of official exchange bureaus and banks.
In a notice posted on its website on Wednesday, INTA said it will levy tax on “trade by currency speculators” whose names are sent to the tax authority by the Central Bank of Iran and other supervisory bodies.   
The new measures will be levied in line with Article 163 of the Direct Tax Act, the notice said. 
INTA in the notice did not say how much the currency dealers would be taxed. However, based on an announcement last December, the tax would be 10% of the currency transactions.