Tax Year

A tax year is the annual accounting period your company uses to report to the IRS. There are two kinds: a calendar year, running January 1 through December 31, and a fiscal year, which ends on the last day of any other month. Nearly every foreign-owned LLC uses the calendar year, because a disregarded entity generally follows its owner's tax year, and individual owners are on the calendar year by default.

The tax year controls every deadline that matters. For a calendar-year foreign-owned single-member LLC, the Form 5472 and pro forma Form 1120 package is due April 15 of the following year. A calendar-year multi-member LLC files Form 1065 with Schedule K-1s by March 15. Form 7004 extends those dates by six months, to October 15 and September 15 respectively.

The first tax year is usually short, and that trips people up. If you formed your LLC on September 10, 2025, your first tax year runs September 10 through December 31, 2025, and your first filing is due April 15, 2026. The company does not need to have made a sale. If you contributed $500 to open the bank account, that alone is a reportable transaction for that short year.

You state the tax year at the top of each return, writing the start and end dates on the pro forma 1120 or Form 1065. Keeping records aligned to that period, bank statements, contribution dates, and distribution amounts, makes the filing quick and accurate. Reporting the wrong period or skipping a short first year can leave a gap the IRS treats as a missed filing, with the $25,000 Form 5472 penalty attached.