Why does a foreign-owned single-member LLC have to file Form 1120 when a US-owned single-member LLC files nothing?

Both can be true at the same time — it's a quirk of US tax classification. Under default rules, a single-member LLC IS disregarded for income-tax classification. But under §6038A reporting rules, a foreign-owned LLC is treated as a corporation for the specific purpose of filing Form 5472.

The conflict:

• §7701 default classification: single-member LLC = disregarded entity. The owner reports the LLC's income on their own return.

• §6038A and Treas. Reg. §301.7701-2: for reporting-only purposes, a 25%+ foreign-owned single-member LLC is treated as a domestic corporation.

These two rules coexist. The LLC is still disregarded for INCOME tax — meaning the foreign owner reports the LLC's income on their own return (Form 1040-NR or, for foreign entities, on their home country tax return). But the LLC must ALSO file a Form 1120 as a "cover return" to deliver Form 5472.

Why this regulation exists:

The IRS implemented §6038A in 1989 and tightened it in 2017 specifically to address tax evasion through foreign-owned US shell entities. Before 2017, a foreign person could create a US LLC, use it to invoice their own offshore company (creating deductible expenses for US tax purposes), and effectively shift profit out of higher-tax jurisdictions — all without leaving a paper trail visible to the IRS.

Form 5472 is the paper trail. By forcing disclosure of related-party transactions, the IRS can:

• Identify suspicious patterns (e.g., recurring $0 invoices, round-number management fees)
• Audit cross-border profit shifting
• Coordinate with foreign tax authorities under treaty information-sharing
• Apply transfer-pricing rules retrospectively

Practical consequences for the EA candidate:

1. Always check for foreign ownership. When a client describes their LLC structure, ask "who owns this?" If a foreign individual or entity, Form 5472 + Form 1120 are required.

1. Sleeper trap — change in ownership. If a US-owned LLC is sold mid-year to a foreign buyer, the LLC must file Form 5472 + Form 1120 for the part of the year after the sale. Easy to miss.

1. Spouse rules. If the LLC is owned by a US citizen and their non-resident-alien (NRA) spouse holds it jointly, things get complicated. Generally, NRA spouses are treated as foreign for §6038A purposes.

1. Trust ownership. A foreign trust owning a US LLC triggers §6038A. The reporting falls on the LLC, not the trust.

1. Multi-tier structures. If a foreign individual owns a foreign corp that owns a US LLC, both layers require disclosure (the foreign corp may also have to file Form 5472).

Penalty calculation:

$25,000 minimum per Form 5472 per year. For a 3-year non-filing case with 2 related parties, that's $25,000 × 3 years × 2 forms = $150,000 of penalties. Penalties can compound if filings are not corrected after IRS notice.

Voluntary disclosure:

If a client realises they've been non-filing, the IRS has a streamlined offshore voluntary disclosure program that can reduce penalties to ~5% of unreported value (much less than the cumulative $25K-per-form-per-year). EAs help clients calculate whether voluntary disclosure makes sense.