Form 5472 for UK LLC Owners: What British Founders Must File

Thousands of British founders form US LLCs to access Stripe, sell on Amazon US, run a SaaS, or invoice American clients. Many form through Stripe Atlas, doola, or directly in Wyoming, Delaware, or New Mexico. What very few are told at sign-up is that a US LLC owned by a non-US person sits inside Internal Revenue Code section 6038A and must file Form 5472 every year it has a reportable transaction with its owner.

Your residence in the United Kingdom does not change this. The rule keys off who owns the entity, not where the income is earned or where you live. Since 2017, a foreign-owned single-member LLC is treated as a corporation solely for this reporting purpose under Treasury Decision 9796, even though it remains a disregarded entity for everything else.

If you are unsure whether your specific situation triggers a filing, the do-I-need-to-file qualifier walks through it in under a minute, and the foreign-owned single-member LLC guide explains your exact entity type in depth.

This is the single most misunderstood point among UK founders. People assume “no income means no filing.” That is wrong. Form 5472 reports money moving between you and your LLC, not the LLC's profit. The first wire you send from your British bank account to capitalise the company is itself a reportable transaction.

Because forming and funding the LLC always moves money from the owner, virtually every British-owned single-member LLC has a reportable transaction in its first year. The capital contribution explainer shows why even a single funding deposit makes the form mandatory.

The IRS defines a reportable transaction broadly. Any transfer of money or property between the US reporting entity and a related foreign party falls inside it. For a British single-owner LLC, the related foreign party is usually you — and sometimes a separate UK company you also control.

The categories that matter for a UK founder

Monetary transactions for services, rent, royalties, and commissions are reported in Part IV. Contributions, loans, loan repayments, and distributions — the most common items for a founder — are reported in Parts V and VI. There is no minimum threshold: a single dollar moving between you and the LLC is reportable.

The reportable transaction guide lists every category with examples. The practical takeaway for British owners: if money ever moved between your personal accounts and the LLC, you have a reportable transaction and must file.

Form 5472 cannot be mailed alone. The regulations require it to be attached to an income-tax return, and the only return available to a disregarded entity is a pro forma Form 1120. “Pro forma” means “as a matter of form” — it is a cover sheet, not a real tax computation. A British owner pays no US entity-level income tax on a disregarded LLC.

The complete package is one pro forma 1120 with one Form 5472 stapled behind it. The pro forma 1120 guide and the Form 5472 + pro forma 1120 overview show the exact fields, line by line.

Every LLC needs an Employer Identification Number (EIN) before it can file Form 5472. UK founders without a US Social Security Number cannot use the IRS online EIN application, which requires an SSN or ITIN for the responsible party. Instead, you complete Form SS-4 and submit it by fax or post.

On line 7b of Form SS-4 a British applicant writes “Foreign” where an SSN or ITIN would go. You do not need an ITIN to obtain an EIN for the LLC. The EIN is what links your filings to the entity, so apply early — you cannot file Form 5472 without it.

Form 5472 carries one of the harshest information-return penalties in the US tax code, and it applies to British owners exactly as it applies to anyone else. The base penalty is $25,000 for each form not filed, filed late, or filed substantially incomplete. Because there is no statute of limitations on an unfiled information return, a year you missed three years ago can still be assessed today.

The Form 5472 penalty guide and the penalty calculator show your exposure by number of unfiled years. If you have already missed a year, see the catch-up filing guide for how to get current.

The extension moves only the filing deadline. For a disregarded entity there is no US tax to pay, so there is nothing else to extend. File Form 7004 by April 15 to claim the six-month extension to October 15. See the deadline guide and the Form 7004 extension guide for details.

British founders often forget that the US tax year runs to December 31 regardless of the UK's April-to-April tax year. The Form 5472 deadline keys off the US calendar year, not the UK fiscal year.

This is a critical and widely misunderstood point: there is no e-file path for a foreign-owned disregarded entity filing a pro forma 1120. Tax software that e-files normal corporate returns will not transmit this package. The only two accepted methods are mail and fax.

For a British founder, an international fax service or a courier with tracking is the most reliable route, since timely filing is the only defence against the $25,000 penalty. The how-to-file guide walks through every step, and the fax number guide confirms the current IRS number.

The United States and the United Kingdom have a comprehensive income tax treaty that allocates taxing rights and relieves double taxation. British founders often assume the treaty means “no US filings.” That is a mistake. The treaty governs tax liability — who taxes what income — but Form 5472 is a disclosure, not a tax.

Why a treaty cannot waive an information return

Information-reporting obligations under IRC section 6038A exist so the IRS can see cross-border transactions, even when no US tax is ultimately owed. A treaty position might reduce or eliminate the tax on a stream of income, but you still have to disclose the underlying transactions. The penalty for non-filing — $25,000 — applies regardless of any treaty benefit.

In short: the treaty may change what you owe, but not what you must report. A British owner of a US LLC files Form 5472 the same as any other foreign owner. For complex treaty positions on income tax itself, consult a licensed cross-border tax adviser — that is separate from the Form 5472 information return.

Beneficial Ownership Information (BOI) reporting under the Corporate Transparency Act caused a great deal of confusion for foreign founders. The position as of the FinCEN March 2025 interim final rule is clear: US-formed companies are exempt. A Wyoming, Delaware, or New Mexico LLC owned by a British citizen is a US-formed entity and does not file BOI.

Do not confuse the two: BOI is a FinCEN ownership disclosure; Form 5472 is an IRS information return. The BOI vs Form 5472 comparison explains how they differ, and the BOI overview covers the exemption in detail.

Form 5472 is only half of the section 6038A obligation. The statute also imposes a record-keeping requirement. The LLC must maintain permanent books that substantiate the amount and nature of each reportable transaction with you, the British owner.

What a UK founder should keep

Keep bank statements showing each transfer between your UK accounts and the LLC, the operating agreement, any loan agreements, invoices, and a simple ledger of money moving between you and the company. If the IRS examines the entity and the records are missing, a separate $25,000 penalty applies under section 6038A(d) for failure to maintain records — on top of any failure-to-file penalty.

Clean records also let the LLC respond quickly if the IRS requests documents. Keeping organised books turns a stressful examination into a routine document request.

Most penalties do not come from fraud. They come from simple, avoidable errors by British founders who were never told the rules at sign-up. The mistakes below cause the overwhelming majority of problems.

Each is preventable. A specialist who files Form 5472 every day catches all of them automatically. If you have already missed a year, the missed-filing guide explains your options.

Many British founders form their LLC through doola or Stripe Atlas and only later realise the annual Form 5472 is a separate, recurring duty. For a flat $299, form5472.tax prepares Form 5472 and the pro forma 1120, has a specialist review it, and files it correctly — saving $248versus form5472.online and up to $1,700 versus doola.

One important boundary: form5472.tax does not represent clients before the IRS. We prepare and file the return. If you face a penalty notice or an examination, options such as Form 843 reasonable cause, a Form 2848 power of attorney, or voluntary disclosure exist, but representation requires a licensed tax attorney, CPA, or enrolled agent — we will refer you to one. See the doola alternative and switch-from-doola guide if you are leaving a bundled provider.

British founders often receive a W-8BEN or W-8BEN-E request from a US payer, bank, or platform such as Stripe or a US marketplace. These forms are not filed with the IRS by you; they are given to the payer to certify your foreign status and claim any treaty rate on US-source withholding. They are completely separate from Form 5472.

Use the W-8BEN guide if you are an individual and the W-8BEN-E guide if a payer asked your entity to certify. The W-8BEN vs W-8BEN-E comparison explains which one applies. Whichever you sign, the LLC still files Form 5472 with the IRS.

Form 5472 asks for the foreign owner's US taxpayer identification number. A British founder usually does not have one — no SSN and no ITIN — and that is fine. Where a US TIN would go, you instead supply a reference ID number: a consistent identifier you assign yourself so the IRS can match the owner across years. The instructions allow any combination of letters and numbers up to 50 characters.

The one rule that trips British founders up: consistency. If you use one code this year and a different one next year, the IRS cannot link the filings to the same owner, which can flag the return. The reference ID number guide explains exactly what to enter and where, and the Form 5472 instructions walk through each line.

Many British entrepreneurs hold more than one US LLC — a holding company, an operating company, or a separate entity per brand. There is no consolidated or group filing for foreign-owned disregarded entities. Each LLC files its own pro forma 1120 with its own Form 5472, using that entity's own EIN. Mailing or faxing one combined package for several LLCs is not permitted.

The practical lesson for a British owner with a portfolio of entities is to track each one separately. A single missed LLC carries the full $25,000 penalty on its own. If any entity in your group is inactive, the dormant LLC guide explains whether it still has to file.

British founders often let an LLC go dormant — they paused the business but never dissolved it. “Dormant” does not automatically mean “no filing.” Form 5472 turns on whether a reportable transaction occurred, not on whether the business traded. If you paid the registered-agent fee, the state renewal, or a bank charge from your personal account, that can be a reportable transaction between you and the LLC.

Because the bar is so low, most dormant LLCs still file. When in doubt, file — a protective Form 5472 costs nothing in penalties, while a wrongly skipped one risks $25,000. The dormant LLC guide works through the edge cases for inactive British-owned entities.

For a British owner, banking is where most reportable transactions actually happen. To capitalise a US LLC you typically wire money from a UK bank — Wise, Revolut, a high-street bank — into the LLC's US business account (often Mercury, Relay, or a similar provider). That very first inbound wire is a capital contribution, and it is reportable on Form 5472.

Later, if the LLC sends money back to you — whether you call it a distribution, a loan repayment, or a reimbursement — that outbound flow is also reportable. The IRS does not care about the label you use; it cares that money moved between the entity and its foreign owner. This is why a clean banking trail matters so much: the figures on Form 5472 must match what your statements show.

A common British scenario is paying a US vendor or the formation agent from your personal UK card because the LLC's account is not open yet. That payment-on-behalf-of is itself a reportable transaction — the owner funded an LLC expense. The capital contribution explainer and the reportable transaction guide show how to classify each banking movement correctly.

Because Form 5472 has no statute of limitations, a year you missed remains open indefinitely — but that also means you can still fix it. The route is to prepare each delinquent year as a separate package (one pro forma 1120 and one Form 5472 per year) and submit them, ideally with a written reasonable-cause statement explaining why the filing was late.

One boundary to be clear about: form5472.tax does not represent clients before the IRS. We prepare and file the catch-up returns. If the IRS has already assessed a penalty and you want it abated, that requires a licensed attorney, CPA, or enrolled agent, and we will refer you. See the catch-up filing guide and the missed-filing guide for the full process.

If a British founder cannot assemble the package by April 15 — perhaps the EIN has not arrived or the bank records are still being gathered — the answer is to file Form 7004, the application for an automatic extension of time. Submitted on time, it moves the Form 5472 and pro forma 1120 deadline to October 15 with no need to explain why.

One caution: an extension only buys time to file, not to ignore the obligation. Missing the extended October 15 deadline puts the $25,000 penalty back in play. The Form 7004 guide and the deadline guide explain the timing for British-owned entities in detail.

Form 5472 reports transactions between the US LLC and its related parties. For a British single-member LLC, you — the 100% owner — are the obvious related party. But the definition is wider: it captures any 25%-or-more foreign owner and any person or entity related to them under the attribution rules of IRC section 318.

This matters when a British founder routes money through more than one entity — for example, a UK limited company that invoices the US LLC, or vice versa. Those inter-company flows are reportable related-party transactions. The IRC 6038A guide sets out the related-party rules, and the Form 5472 overview shows where each party is entered on the form.

A frequent British misconception is that “I already declare this to HMRC, so the US side is covered.” The two systems do not overlap. HMRC handles your UK Income Tax, Corporation Tax, and VAT. The IRS handles US filings, and Form 5472 is one of them. Filing one does not discharge the other.

You may still owe UK tax on profits the LLC earns, depending on your UK residence and how the income is characterised — that is a question for a UK accountant. But regardless of the UK answer, the US LLC files Form 5472 whenever it has a reportable transaction. For how the US side fits with the rest of your US compliance, see the LLC annual compliance guide.

Filing on time is necessary but not sufficient. The IRS can assess the full $25,000 penalty when a Form 5472 is filed but is substantially incomplete or incorrect. For British founders doing it themselves, the errors below are the ones that most often turn a filed form into a penalised one.

The defence is simple: complete every required field, attach the pro forma 1120, reuse the same reference ID each year, and file by mail or fax. A specialist review catches these before the package goes out. The completed Form 5472 example shows a correctly filled form, and the instructions guide covers each line.