Can I Choose/Change To A Fiscal Year?
Generally, a regular "C" corporation - which is not a personal service corporation - can elect whatever fiscal year it wants. This election is made simply by filing the first tax return for that period of 12 months or less.
If a corporation desires to change its fiscal year after that, it must request permission to do so from the Internal Revenue Service.
A personal service corporation must generally file on a calendar year, unless it meets the requirements of IRC 444 for election of a fiscal year.