A foreign-owned US company usually has federal tax filings, state compliance, registered-agent renewals, and bookkeeping tasks every year—even if it made no profit or had no US customers. The exact calendar depends first on whether your company is a single-member LLC, multi-member LLC, or C-Corp, and second on its formation and operating states.
For a calendar-year Delaware company, the headline dates are March 1 for a corporation’s Delaware annual report and franchise tax, April 15 for many federal filings, and June 1 for a Delaware LLC’s $300 annual tax. Foreign-owned single-member LLCs must pay particular attention to Form 5472 with a pro-forma Form 1120 because late or incomplete filing can trigger a $25,000 penalty.
LLC and C-Corp obligations at a glance
Do not apply one entity type’s calendar to another. A Delaware LLC does not file the same annual state report as a Delaware corporation, while a C-Corp normally files a complete Form 1120 rather than the pro-forma return used by a foreign-owned disregarded LLC.
| Obligation | Foreign-owned single-member LLC | C-Corp |
|---|---|---|
| Federal income tax return | Usually Form 5472 attached to pro-forma Form 1120 when reportable transactions occurred | Form 1120 |
| Typical calendar-year deadline | April 15 | April 15 |
| Delaware annual obligation | $300 annual tax due June 1; no annual report | Annual report and franchise tax due March 1 |
| Federal extension | Form 7004 generally extends the filing deadline | Form 7004 generally extends the filing deadline |
| Bookkeeping | Needed to identify owner-company transactions and support filings | Needed for the balance sheet, income statement, tax return, and shareholder records |
Important: A multi-member LLC is generally taxed as a partnership and may need Form 1065, typically due March 15 for a calendar-year entity. An LLC that elected corporate taxation follows different federal rules.
January and February: close the books and collect records
January: complete the year-end bookkeeping close
Reconcile every bank, card, Stripe, PayPal, Mercury, Wise, and other financial account through December 31. Categorize revenue, operating expenses, owner contributions, owner withdrawals, loans, reimbursements, and payments between the company and related parties.
For a foreign-owned disregarded LLC, reportable transactions can include money contributed by the owner, distributions, payments for services, loans, and other transfers. “No revenue” does not necessarily mean “no Form 5472 filing.”
- Download December statements and annual transaction exports.
- Reconcile balances in QuickBooks, Xero, or your accounting ledger.
- Record unpaid bills, invoices, processor fees, refunds, and chargebacks.
- Confirm the legal name, EIN, address, ownership, and tax classification.
- List transactions with owners and other related foreign parties.
February: prepare Delaware corporation filings
If you operate a Delaware C-Corp, review the annual report notice and calculate franchise tax before March 1. Delaware corporations generally calculate tax under the Authorized Shares Method or Assumed Par Value Capital Method. The amount can differ substantially, so compare the permitted methods rather than accepting an unexpectedly large default calculation.
Also confirm the directors, officers, principal business address, registered agent, and capitalization records. Delaware LLC owners can use February to verify that $300 is reserved for the June payment.
March and April: the main filing season
March 1: Delaware corporation deadline
The Delaware franchise tax deadline for domestic corporations is March 1. The annual report and franchise tax are filed together. Delaware corporations generally owe at least the statutory minimum franchise tax, plus the annual report filing fee; the final amount depends on the calculation method and company details.
This deadline applies even if the corporation had no activity. Late filing can create penalties and interest and eventually affect the company’s good standing.
March 15: partnerships and S-Corporations
A calendar-year multi-member LLC taxed as a partnership generally files Form 1065 by March 15 and issues Schedule K-1 to each partner. A qualifying entity with an S-Corporation election generally files Form 1120-S by the same date, although S-Corporation ownership restrictions mean this election is often unavailable to nonresident alien founders.
April 15: Form 5472, pro-forma 1120, and C-Corp returns
A calendar-year, foreign-owned single-member LLC treated as a disregarded entity generally files Form 5472 attached to a pro-forma Form 1120 when it has reportable transactions. The filing must follow the IRS method applicable to foreign-owned US disregarded entities; it is not simply a normal personal tax attachment.
A calendar-year C-Corp generally files Form 1120 and pays any federal corporate income tax due by April 15. A filing extension generally does not extend the time to pay tax. State corporate returns and payments may also be due around this period.
Form 5472 deserves priority: the base penalty for failure to file a correct and timely form is $25,000, with additional penalties possible if noncompliance continues after IRS notice.
May through August: state and operational compliance
May: review other state annual reports
Delaware formation does not eliminate compliance elsewhere. If your company is registered, has employees, maintains an office, stores inventory, or otherwise does business in another state, it may have annual reports, franchise taxes, income taxes, payroll filings, or sales-tax obligations there.
State deadlines vary. For example, some are fixed dates, while others follow the company’s anniversary month. Check every state where the business is formed, foreign-qualified, employing people, or potentially creating tax nexus.
June 1: Delaware LLC annual tax
Every Delaware LLC generally pays a flat $300 annual tax by June 1. Unlike a Delaware corporation, an LLC does not file a Delaware annual report with this payment. The obligation normally remains even if the LLC had no income or transactions.
July and August: midyear review
Run a midyear profit-and-loss statement and balance sheet. Reconcile accounts through June 30, update forecasts, and determine whether a C-Corp should make estimated federal or state tax payments. Review sales-tax registrations if your customer locations, transaction volume, products, or fulfillment model changed.
Check whether new founders, investors, employees, contractors, addresses, or lines of business require updates to tax, payroll, licensing, insurance, banking, or state records.
September through December: renew, verify, and prepare
September and October: extension deadlines
For calendar-year entities with valid extensions, partnership and S-Corporation returns are generally due September 15. Form 1120 and a foreign-owned disregarded entity’s Form 5472 with pro-forma Form 1120 are generally due October 15.
Do not wait until the extension deadline to reconstruct owner transfers. Compare the ledger with bank statements and documentation such as loan agreements, invoices, reimbursement schedules, and capital approvals.
November: registered-agent renewal and good standing
Your registered agent must remain active in every state where the company is registered. Renewal timing depends on the provider and service start date, so it is not always tied to the state filing deadline.
- Confirm the agent has the correct email and contact person.
- Pay renewal invoices before service lapses.
- Check the company’s status in each state registry.
- Order a certificate of good standing only when a bank, investor, marketplace, or counterparty requires one.
December: pre-close planning
Collect missing W-9 and W-8 forms, review contractor payment records, document year-end owner transactions, and schedule the January close. C-Corps should update cap-table and board records and assess estimated tax payments. If you plan to dissolve, start before year-end rather than simply stopping payments; tax and state obligations can continue until formal closure is completed.
Beneficial ownership reporting: verify the current rule
Beneficial ownership information reporting under the Corporate Transparency Act changed materially in 2025. Under FinCEN’s interim final rule issued in March 2025, entities created in the United States—including domestic LLCs and corporations—were exempted from BOI reporting. Certain foreign entities registered to do business in a US state may still have reporting obligations, subject to the current rule and exemptions.
This area has experienced litigation and rule changes, so do not rely on an old incorporation checklist or automated reminder. Before any ownership change or new registration, verify the current FinCEN rule and official deadlines. BOI reporting is separate from IRS Form 5472 and state annual reports.
Your annual compliance workflow
- Classify the entity: disregarded LLC, partnership, C-Corp, or another tax election.
- List jurisdictions: formation state plus every state where the company is registered or operating.
- Build the calendar: include March 1, April 15, June 1, extension dates, state deadlines, and agent renewal.
- Close monthly: reconcile bank and payment accounts instead of rebuilding 12 months at tax time.
- Tag related-party transactions: document owner funding, withdrawals, loans, fees, and reimbursements.
- File or extend on time: remember that extensions generally extend filing, not tax payment.
- Store proof: retain accepted filings, payment confirmations, notices, returns, and supporting ledgers.
Frequently asked questions
Does an inactive foreign-owned LLC still file Form 5472?
Possibly. Formation costs, owner contributions, withdrawals, and other owner-company transfers may be reportable transactions even without sales. Review the ledger with a US tax professional.
Is the Delaware LLC deadline April 15?
No. April 15 is commonly the federal filing deadline for a calendar-year foreign-owned disregarded LLC. The Delaware LLC annual tax of $300 is due June 1.
Can I extend Form 5472?
A timely Form 7004 generally extends the deadline for the pro-forma Form 1120 and attached Form 5472. Prepare the extension carefully and retain filing evidence.
Does a Delaware C-Corp pay franchise tax if it had no revenue?
Yes. Delaware franchise tax and the annual report requirement are based on maintaining the corporation, not on whether it generated revenue.
Do Stripe or Mercury handle these filings?
No. They may provide account statements and transaction exports, but bookkeeping, tax returns, state reports, and registered-agent compliance remain the company’s responsibility.
When Founder Portal can help
Founder Portal can help you map the correct LLC or C-Corp calendar, organize bookkeeping and owner transactions, and coordinate the filings needed to keep your US company operational.