Here is the relevant extract from that source:
'10. Tax treatment of income from dividends, interest and royalties Pursuant to Law 4172/2013, in conjunction with Ministerial Circular 1042/26.01.2015, the income acquired by a natural person in cash or in kind in the form of dividends, interest and royalties is considered income from capital. In brief:
• For natural persons income from dividends is taxed with a 10% coefficient, income from interest is taxed with a 15% coefficient, and income from royalties is taxed with a 20% coefficient.
• For legal persons or legal entities having their residence for tax purposes in Greece, with regard to the income stated by them, there is tax withholding with a 10% coefficient for dividends, with a 15% coefficient for interest and with a 20% coefficient for royalties.
• For a domestic natural person or a natural or legal person or a legal entity which does not have its residence for tax purposes and does not keep a permanent establishment in Greece (i.e. with an office, a branch, etc.), tax withholding on all the dividends, interest and royalties exhausts their tax obligation.
• For natural persons exercising a business activity, by virtue of the royalties they hold (e.g. artists, authors, etc.), for income from royalties whether of domestic or foreign origin, the exhaustion of the tax obligation does not apply, but they are taxed as income from a business activity.
• No 10% withholding is implemented on profits exported by a permanent residence in Greece (branch) of a foreign company to its central office abroad, since the branch has no legal personality.
• For a domestic legal person or a legal entity, whether for-profit or non-profit, or a permanent establishment in Greece of a foreign legal person, income from dividends or interest, tax withholding is implemented without exhausting the tax obligation, it is taxed as income from a business activity and the tax withheld is set off with the income tax.
• For a natural person, resident abroad for tax purposes, the income from dividends or interest abroad, regardless of whether they are entered in Greece or not, must be entered in such person’s annual income tax statement.
• For a natural person, resident abroad for tax purposes, if income from interest abroad has been imported in Greece, tax withholding is implemented on the gross amount of the interest and withholding is carried out by the domestic financial-credit institution or trustee which intervenes as a payment body and exhausts the tax obligation of the natural person.
• Provided that the beneficiaries of the income from dividends, interest and royalties, whether natural persons or legal persons or legal entities, do not have their residence for tax purposes in Greece or do not keep a permanent residence in Greece, but they are residents of a state with which there is a D.T.T., the provisions of the bilateral treaty shall apply, by virtue of increased typical power.'
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