The 15 October 2026 deadline is days away for calendar-year foreign-owned US single-member LLCs that timely filed Form 7004. If your LLC’s Form 5472 package is not ready, act now: a late or substantially incomplete filing can trigger a $25,000 penalty.
Check whether you must file by 15 October
This deadline generally applies to you if:
- You own a US domestic single-member LLC as a foreign person, and the LLC is treated as a disregarded entity for US tax purposes.
- The LLC had reportable transactions with you or another related party during its tax year.
- Its calendar-year Form 5472 filing was extended by a timely Form 7004.
The IRS Form 5472 instructions require a foreign-owned US disregarded entity to attach Form 5472 to a pro forma Form 1120. A timely Form 7004 can extend the filing deadline. For an eligible calendar-year filer with an extension, 15 October 2026 is the final extended deadline. No further extension is available.
The IRS’s fourth-quarter tax calendar also lists 15 October for calendar-year corporations that timely requested an extension.
There is a separate individual filing deadline: a nonresident individual who received US wages subject to withholding and timely filed Form 4868 generally must file Form 1040-NR by 15 October. If you received no US wages subject to withholding and timely filed Form 4868, the deadline is generally 15 December 2026. Check which rule applies to you.
Assemble the complete filing package
For a foreign-owned US LLC, the package includes:
- Form 5472, completed accurately for reportable transactions with the foreign owner or other related party.
- A pro forma Form 1120 attached to Form 5472. The IRS instructions specify which limited Form 1120 fields to complete for a foreign-owned disregarded entity.
- Supporting transaction records, including amounts, dates, descriptions and relevant exchange-rate calculations.
Foreign-owned US disregarded entities cannot e-file this package. The IRS directs filers to submit it by fax or mail to the dedicated Ogden PIN Unit address in the Form 5472 instructions. Use the current IRS instructions to verify the filing method and address before sending.
See what this means for an international seller
Imagine a UK or Australian seller operating a Wyoming or Delaware single-member LLC. The seller runs an Amazon FBA business and a Shopify store, holds inventory in several US states, and sells to US customers.
For the LLC’s Form 5472, review transactions between the LLC and its foreign owner or other related parties. Relevant items may include:
- Capital contributions made by the owner.
- Distributions or owner draws.
- Reimbursements between the owner and LLC.
- Loans to or from the owner, including balances and interest where relevant.
Amazon and Shopify sales to unrelated customers are not, simply because they are platform sales, transactions with the foreign owner. Do not confuse platform revenue with related-party reporting. Keep marketplace statements and sales records for the LLC’s broader accounting, and identify owner-related transactions separately.
A late or substantially incomplete Form 5472 can carry a $25,000 initial penalty. The IRS international information reporting penalties page says that if the IRS sends a notice and the failure continues beyond 90 days, a further $25,000 may apply for each 30-day period or part of a period. There is no maximum continuation penalty.
Understand the reasonable-cause route
If you have already missed a deadline, relief may be possible, but it is not automatic. IRS Chief Counsel Advice CCA 202617012, released on 24 April 2026, discusses liberal application of reasonable-cause relief for qualifying small corporations under Treasury Regulation § 1.6038A-4(b)(2)(ii).
The four prerequisites are:
- Overall gross receipts of $20 million or less for the tax year.
- No knowledge of the Section 6038A requirements.
- Limited presence in and contact with the United States.
- Prompt and full compliance with IRS requests to file Form 5472 and provide relevant books, records and materials.
You must establish the facts in a written statement signed under penalties of perjury. The CCA is not precedent, and meeting the four conditions does not erase the filing obligation. It addresses possible penalty relief, not permission to leave the return unfiled.
If you missed the date or receive a CP215 notice, act promptly
If the deadline has passed, do not wait for a notice. Prepare and send the complete Form 5472 and pro forma Form 1120 package to the Ogden PIN Unit using the current IRS filing instructions. Keep proof of submission and copies of everything filed.
If you receive a CP215 penalty notice, read it carefully and follow its response instructions and deadlines. CP215 is commonly used when the IRS assesses the Form 5472 penalty. Correcting the filing and responding to the notice are separate steps: send the missing package, then submit a supported reasonable-cause statement if the facts justify a request for relief. For account questions, the IRS International Taxpayer Service Call Center handles international tax account enquiries.
Take the nonfiler enforcement restart seriously
The 15 October filing cliff comes as the IRS is moving stalled nonfiler cases forward. TIGTA’s report 2026308047fr, released in September 2026, found that as of 30 June 2025, 38,824 high-priority cases involving 33,653 taxpayers remained in first-notice status. Those cases represented about $15.7 billion in potential tax assessments. The IRS advanced the cases in March 2026 after TIGTA raised the issue. The Journal of Accountancy’s 15 September 2026 report summarises the findings.
This report concerns high-income nonfilers and does not mean every Form 5472 filer will automatically receive a notice. It does show why you should not assume that an IRS backlog will protect you from follow-up.
For individuals, the IRS describes a separate process in FS-2024-06 on nonfiler compliance alerts. A CP59 may prompt a taxpayer to file a signed return, respond using Form 15103 where included, or explain why no return is required. If the taxpayer does not respond, the IRS may prepare a substitute return and issue a CP3219N notice, which generally gives 90 days to file or petition the Tax Court. These individual procedures are not the same as the Form 5472 process, but both underline the value of prompt, complete responses.
