Section 51National Internal Revenue Code of 1997 (Republic Act No. 8424), Sec. 51

Individual Return. -

(A) Requirements. -

(1) Except as provided in paragraph (2) of this Subsection, the following individuals are required to file an income tax return:

(a) Every Filipino citizen residing in the Philippines;

(b) Every Filipino citizen residing outside the Philippines, on his income from sources within the Philippines;

(c) Every alien residing in the Philippines, on income derived from sources within the Philippines; and

(d) Every nonresident alien engaged in trade or business or in the exercise of profession in the Philippines.

(2) The following individuals shall not be required to file an income tax return;

(a) An individual whose gross income does not exceed his total personal and additional exemptions for dependents under Section 35: Provided, That a citizen of the Philippines and any alien individual engaged in business or practice of profession within the Philippine shall file an income tax return, regardless of the amount of gross income;

(b) An individual with respect to pure compensation income, as defined in Section 32 (A)(1), derived from sources within the Philippines, the income tax on which has been correctly withheld under the provisions of Section 79 of this Code: Provided, That an individual deriving compensation concurrently from two or more employers at any time during the taxable year shall file an income tax return: Provided, further, That an individual whose compensation income derived from sources within the Philippines exceeds Sixty thousand pesos (P60,000) shall also file an income tax return;

(c) An individual whose sole income has been subjected to final withholding tax pursuant to Section 57(A) of this Code; and

(d) An individual who is exempt from income tax pursuant to the provisions of this Code and other laws, general or special.

(3) The forgoing notwithstanding, any individual not required to file an income tax return may nevertheless be required to file an information return pursuant to rules and regulations prescribed by the Secretary of Finance, upon recommendation of the Commissioner.

(4) The income tax return shall be filed in duplicate by the following persons:

(a) A resident citizen - on his income from all sources;

(b) A nonresident citizen - on his income derived from sources within the Philippines;

(c) A resident alien - on his income derived from sources within the Philippines; and

(d) A nonresident alien engaged in trade or business in the Philippines - on his income derived from sources within the Philippines.

(B) Where to File. - Except in cases where the Commissioner otherwise permits, the return shall be filed with an authorized agent bank, Revenue District Officer, Collection Agent or duly authorized Treasurer of the city or municipality in which such person has his legal residence or principal place of business in the Philippines, or if there be no legal residence or place of business in the Philippines, with the Office of the Commissioner.

(C) When to File. -

(1) The return of any individual specified above shall be filed on or before the fifteenth (15th) day of April of each year covering income for the preceding taxable year.

(2) Individuals subject to tax on capital gains;

(a) From the sale or exchange of shares of stock not traded thru a local stock exchange as prescribed under Section 24(c) shall file a return within thirty (30) days after each transaction and a final consolidated return on or before April 15 of each year covering all stock transactions of the preceding taxable year; and

(b) From the sale or disposition of real property under Section 24(D) shall file a return within thirty (30) days following each sale or other disposition.

(D) Husband and Wife. - Married individuals, whether citizens, resident or nonresident aliens, who do not derive income purely from compensation, shall file a return for the taxable year to include the income of both spouses, but where it is impracticable for the spouses to file one return, each spouse may file a separate return of income but the returns so filed shall be consolidated by the Bureau for purposes of verification for the taxable year.

(E) Return of Parent to Include Income of Children. - The income of unmarried minors derived from properly received from a living parent shall be included in the return of the parent, except (1) when the donor's tax has been paid on such property, or (2) when the transfer of such property is exempt from donor's tax.

(F) Persons Under Disability. - If the taxpayer is unable to make his own return, the return may be made by his duly authorized agent or representative or by the guardian or other person charged with the care of his person or property, the principal and his representative or guardian assuming the responsibility of making the return and incurring penalties provided for erroneous, false or fraudulent returns.

(G) Signature Presumed Correct. - The fact that an individual's name is signed to a filed return shall be prima facie evidence for all purposes that the return was actually signed by him.