A pro forma Form 1120 is a partially completed US corporation income tax return used as a cover sheet for Form 5472 when a foreign-owned disregarded LLC files. It is not a full corporate return and does not compute corporate tax - it exists so the information return has something to attach to.
Why does Pro forma Form 1120 matter for founders?
Founders often search for it separately and conclude they have somehow become a corporation. They have not. It is a filing mechanism, and the substantive obligation is the attached Form 5472 with its $25,000 failure-to-file penalty.
Where can I read more about Pro forma Form 1120?
Note: A plain-English definition for orientation, not legal or tax advice. Rules change - last checked 2026-07-21.