Unlike stock investments and mutual funds, a designated account for CFDs doesn't exist. Therefore, a tax return is usually required when profits are generated.
CFDs are subject to separate self-assessment taxation (miscellaneous income). The tax rate is a flat rate of 20.315% (income tax 15% + resident tax 5% + special reconstruction income tax 0.315%). In addition, losses carried forward for three years and profit and loss can be offset, but these cannot be offset against profit and loss from stock investments or mutual funds. Profit and loss can be offset with those from futures trading, FX, etc. For further details, please consult with the tax office or a tax accountant or other professional for confirmation.