Section 90National Internal Revenue Code of 1997 (Republic Act No. 8424), Sec. 90

Estate Tax Returns. -

(A) Requirements. - In all cases of transfers subject to the tax imposed herein, or where, though exempt from tax, the gross value of the estate exceeds Two hundred thousand pesos (P200,000), or regardless of the gross value of the estate, where the said estate consists of registered or registrable property such as real property, motor vehicle, shares of stock or other similar property for which a clearance from the Bureau of Internal Revenue is required as a condition precedent for the transfer of ownership thereof in the name of the transferee, the executor, or the administrator, or any of the legal heirs, as the case may be, shall file a return under oath in duplicate, setting forth:

(1) The value of the gross estate of the decedent at the time of his death, or in case of a nonresident, not a citizen of the Philippines, of that part of his gross estate situated in the Philippines;

(2) The deductions allowed from gross estate in determining the estate as defined in Section 86; and

(3) Such part of such information as may at the time be ascertainable and such supplemental data as may be necessary to establish the correct taxes.

Provided, however, That estate tax returns showing a gross value exceeding Two million pesos (P2,000,000) shall be supported with a statement duly certified to by a Certified Public Accountant containing the following:

(a) Itemized assets of the decedent with their corresponding gross value at the time of his death, or in the case of a nonresident, not a citizen of the Philippines, of that part of his gross estate situated in the Philippines;

(b) Itemized deductions from gross estate allowed in Section 86; and

(c) The amount of tax due whether paid or still due and outstanding.

(B) Time for filing. - For the purpose of determining the estate tax provided for in Section 84 of this Code, the estate tax return required under the preceding Subsection (A) shall be filed within six (6) months from the decedent's death.

A certified copy of the schedule of partition and the order of the court approving the same shall be furnished the Commissioner within thirty (30) after the promulgation of such order.

(C) Extension of Time. - The Commissioner shall have authority to grant, in meritorious cases, a reasonable extension not exceeding thirty (30) days for filing the return.

(D) Place of Filing. - Except in cases where the Commissioner otherwise permits, the return required under Subsection (A) shall be filed with an authorized agent bank, or Revenue District Officer, Collection Officer, or duly authorized Treasurer of the city or municipality in which the decedent was domiciled at the time of his death or if there be no legal residence in the Philippines, with the Office of the Commissioner.