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form-5472 pro-forma-1120

The pro-forma 1120, explained

What the pro-forma Form 1120 is, why foreign-owned LLCs need it, exactly which boxes get filled, and the common mistakes we see on it during review.

Reviewed by BorderFile EA/CPA Review Team ·

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If you are a non-US founder with a US LLC, the “pro-forma 1120” is one of the strangest documents in your filing stack. It looks like a corporate tax return. It is not. Its only purpose is to be a cover sheet for your Form 5472. Here is the full story — what it is, why it exists, how to fill it, and the mistakes we see on it most often during review.

Why does a disregarded LLC file a 1120 at all?

A single-member LLC owned by a non-US person is, under default US federal tax rules, a disregarded entity. For most purposes the LLC is invisible to the IRS: it files no 1120, no 1065, no payroll return for the owner. Income and expenses flow up to the owner, who may or may not have a US filing obligation depending on their own facts.

That changed in late 2016. In TD 9796, the Treasury adopted regulations treating a US disregarded entity wholly owned by a foreign person as if it were a corporation for the single, limited purpose of Form 5472 information reporting. The LLC did not become a corporation for income tax; it did not start filing a real 1120. But it did acquire a new information-filing duty: to disclose, each year, the transactions between it and its foreign owner (and other related parties).

Form 5472 was already designed to be attached to a Form 1120. The IRS did not want to invent a new standalone transmittal just for disregarded entities. The simplest answer: use the existing 1120, mark it in a specific way, and attach the 5472. That marked, nearly-blank 1120 is the pro-forma 1120. “Pro-forma” means “for the form’s sake” — a 1120 filled out only to the extent required to make the attachment work.

What goes on it

A pro-forma 1120 for a foreign-owned DE is a very specific document. It is not a complete 1120 with blank schedules. Think of it as a cover letter.

1. The header

At the top of page 1, the IRS requires the words “Foreign-owned U.S. DE”. BorderFile adds this automatically. Filers preparing their own return routinely miss it; without the header, the attachment may not route to the right processing stream inside the IRS and the whole package can be returned.

2. Identifying information

The top identifying boxes are filled in:

  • Name of corporation — the LLC’s legal name, matching the EIN letter character-for-character.
  • Address — a US address. The registered agent’s address is almost always what you want here.
  • EIN — the LLC’s EIN, matching the CP 575 or 147C letter.
  • Date incorporated — the date the state issued the certificate of formation.
  • Total assets — only if required; most pro-forma 1120s show zero or the carrying value from the owner’s records.

3. Signature line

Signed by the owner (or the owner’s authorised representative) with the correct capacity description. For a disregarded entity the usual capacity is “member” or “owner”.

4. The attachments

The real content is in the attachments:

  • Form 5472 itself — the information return.
  • Any supporting statements the Form 5472 instructions call for (for example, a statement describing an “other” transaction category you tagged).

What you do not fill in

  • Schedules C, J, K, L, M-1, M-2 — all blank.
  • Income and deduction lines — all blank or zero.
  • Dividend sections — blank.
  • The tax calculation lines — blank or zero.

The point is that this is not an income tax return. Leaving the schedules blank is correct, not an error.

Why it is faxed, not e-filed

For the ordinary disregarded-entity case, the IRS does not accept e-filing of the 5472 + pro-forma 1120 combination. The IRS does e-file many 1120s, but it specifically carves out foreign-owned disregarded entities because the pro-forma treatment is a documentation convention rather than a true 1120 submission. BorderFile files by fax and stores the fax confirmation page on your filing record. If your bank or auditor later asks “Did BorderFile actually transmit this?”, you have the confirmation page in one click.

The ten mistakes we see most often

When our reviewer runs the checklist against a draft 5472 + pro-forma 1120, a handful of mistakes come up repeatedly. If you are preparing your own filing, this is the list to double-check.

  1. Missing the “Foreign-owned U.S. DE” header. No single thing is more likely to cause a rejection. It belongs at the top of page 1.
  2. Legal name mismatches. The 5472, the pro-forma 1120, and the CP 575 all need to show the same legal name. “ACME Labs LLC” and “Acme Labs, LLC” are different documents to the IRS.
  3. Using a residential address. Technically allowed, but a US registered-agent address is almost always better. Correspondence gets routed through a receiver that is actually paying attention.
  4. Filling in the schedules. The schedules on a pro-forma 1120 are blank by design. Filling them in creates a filing that looks like a real 1120 and may be treated as such.
  5. Signing in the wrong capacity. The owner (or authorised representative) signs as “member” or “owner” of the LLC, not as “president” or “CEO”. The latter is for a C-corp.
  6. Mismatched tax year. The tax year on the pro-forma 1120 must match the LLC’s actual tax year. For most disregarded LLCs that is a calendar year. Fiscal-year LLCs need an attached statement.
  7. Attaching the wrong 5472 version. The 5472 instructions change year to year. Use the version for the tax year you are filing, not for the current calendar year — they are different documents in some seasons.
  8. Forgetting to attach supporting statements. Each “other” transaction tag typically requires a short written statement. The reviewer catches these, but if you prepare yourself, keep a running list of statements that need to be in the final package.
  9. Faxing to the wrong number. The IRS fax number for 5472 can change season to season. Always use the number listed in the current 5472 instructions, not a number you remember from a previous year.
  10. No proof of transmission. A faxed filing is only as useful as the confirmation page. BorderFile stores it automatically; self-filers should keep both the dialled receipt and the full confirmation page.

What a complete pro-forma 1120 package looks like

A finished package has, in order:

  1. The pro-forma 1120 (page 1 only in most cases), with the header, identifying boxes, zero/blank schedules, and the owner’s signature.
  2. Form 5472, fully filled in with the owner’s identifying information, the reporting corporation’s identifying information, and the transaction summary by category.
  3. Any supporting statements referenced on the 5472.
  4. If filed by fax, a cover sheet identifying the LLC, EIN, and tax year.

The whole thing is usually 3–6 pages. The length is deceptive — the specific detail inside those pages is where errors live.

How BorderFile prepares it

Our standard workflow:

  • Intake. Legal name and EIN validated against your CP 575 or 147C.
  • Statements and tagging. Twelve months of coverage, every related-party transaction categorised and totalled.
  • Preparation. Pro-forma 1120 generated with the header, identifying boxes, and signature line. Form 5472 generated with the categorised totals. Supporting statements generated for any “other” tags.
  • Reviewer checklist. Our ten-mistake list above is literally the first ten items on the reviewer checklist. If any one fails, the filing bounces back to intake.
  • EA/CPA sign-off. A different person reviews, signs, and locks the package.
  • E-signature. You sign through our in-house e-sign flow.
  • Fax. We transmit to the current IRS fax number and store the confirmation page.
  • Proof pack. The filing, the fax confirmation, and the review history are packaged into a downloadable PDF + JSON bundle.

If you later get a letter from the IRS about the filing, that proof pack is what you send to your CPA or (if it comes to it) your attorney. Nothing happens in the background; nothing is unprovable.

When a pro-forma 1120 is not the right choice

Three fact patterns look like a pro-forma 1120 case but are not:

  1. A corp election. If the LLC filed Form 8832 to be taxed as a C-corporation, it files a real, fully-populated 1120. The 5472 attaches to the real return, not to a pro-forma.
  2. A multi-member LLC. Default treatment is a partnership (Form 1065). The 5472 attaches to the 1065, not to a pro-forma 1120.
  3. A US owner (even partly). A 5472 is only required when a 25%-or-more owner is a foreign person. If every member is a US person, there is no 5472 and no pro-forma 1120.

If any of these describe you, our eligibility checker routes you to the expert desk — the standard product does not apply.

In one sentence

The pro-forma 1120 is a legally-required cover letter: a nearly-blank 1120 with a specific header, filled identifying information, and a Form 5472 attached — faxed to the IRS, with the confirmation page kept forever.

If you have a question about a specific line on your pro-forma 1120, send us the document at support@borderfile.io and we will tell you what we would do on review.

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