26 CFR 1.6074-3: -3 Extension of time for filing declarations by corporations.

(a) In general. District directors and directors of service centers are authorized to grant a reasonable extension of time for filing a declaration or an amended declaration. Except as provided in paragraph (b) of § 301.6091-1 (relating to hand-carried documents), an application by a corporation for an extension of time for filing such a declaration shall be addressed to the internal revenue officer with whom the corporation is required to file its declaration and must contain a full recital of the causes for the delay.

(b) Addition to tax applicable. An extension of time granted to a corporation for filing a declaration of estimated tax automatically extends the time for paying the estimated tax (without interest) for the same period. However, such extension does not relieve the corporation from the addition to the tax imposed by section 6655, and the period of the underpayment will be determined under section 6655(c) without regard to such extension.