(1) This Convention shall apply to taxes on income imposed on behalf of a Contracting State or of its political or administrative sub-divisions or local authorities, irrespective of the manner in which they are levied.
(2) There shall be regarded as taxes on income all taxes imposed on total income or on elements of income, including taxes on gains from the alienation of movable or immovable property and taxes on the amounts of wages or salaries paid by enterprises.
(3) The existing taxes to which this Convention shall apply are in particular:
- (a) In the case of the Portuguese Republic :
- (i) Personal income-tax (Imposto sobre o Rendimento das Pessoas Singulares - IRS);
- (ii) Corporate Income-tax (Imposto sobre o Rendimento das Pessoas Colectivas - IRC);
- (iii) Local surtax on corporate income-tax (Derrama);
- (hereinafter referred to as "Portuguese tax");
- (b) In the case of the Republic of India:
- (i) the income-tax including any surcharge thereon;
- (hereinafter referred to as "Indian tax").
(4) The Convention shall apply also to any identical or substantially similar taxes which are imposed after the date of signature of the Convention in addition to, or in place of, the existing taxes. The competent authorities of the Contracting States shall notify each other of any substantial changes which have been made in their respective taxation laws.