🇺🇸 US TAX COMPLIANCE
C-Corporation
Tax Return (Form 1120)
Robust, CPA-grade corporate tax preparation for US C-Corporations and startups. Optimize deductions, reconcile financials, and ensure strict IRS compliance.
What is Form 1120?
Form 1120 (U.S. Corporation Income Tax Return) is the primary tax form used by C-Corporations to report their income, gains, losses, deductions, and credits to the IRS. It is used to calculate the corporation's income tax liability at the 21% flat corporate rate.
Unlike LLCs or Partnerships which pass tax burdens to owners, a C-Corporation is a separate taxable entity. This makes the accounting and tax preparation significantly more complex, requiring strict adherence to GAAP, detailed balance sheets, and proper depreciation schedules.
Crucial Details
- **Entity Level Tax:** The corporation itself owes tax on net profits.
- **Foreign Ownership:** 25%+ foreign-owned C-Corps MUST attach Form 5472.
- **Deadline:** April 15th (for standard calendar year entities).
Penalties & Audit Triggers
Corporate returns are highly scrutinized. Errors lead to massive financial exposure.
Late Filing Penalties
Failing to file Form 1120 triggers a penalty of 5% of the unpaid tax for each month the return is late, up to 25%. Minimum penalties apply even if no tax is owed if filed 60+ days late.
Form 5472 Violations
If your C-Corp has foreign ownership and you fail to accurately report related-party transactions, the IRS imposes an immediate, non-negotiable $25,000 penalty per violation.
Underpayment Interest
Corporations must pay estimated taxes. Improper tax calculations or failure to submit quarterly payments results in severe underpayment penalties and compounding interest.
Corporate Filing Inclusions
A precise accounting process to protect corporate assets.
Full 1120 Preparation
Complete calculation of corporate gross income, deductions, taxable income, and tax owed.
Balance Sheet (Schedule L)
Accurate financial reporting of assets, liabilities, and shareholder equity matching your books.
M-1 / M-2 Reconciliation
Reconciling net income per books with income per return, and tracking unappropriated retained earnings.
Foreign Reporting (5472)
If required, preparation of Form 5472 to report transactions between the C-Corp and foreign shareholders.
Depreciation & NOLs
Tracking and applying asset depreciation (Form 4562) and Net Operating Loss carryforwards.
E-Filing Submission
Direct electronic filing to the IRS, securing immediate confirmation of acceptance.
Expert Tax Filing
C-CORPORATION (1120)
*Base fee covers standard C-Corp filings. Highly complex balance sheets, massive asset ledgers, or extensive foreign transaction reporting may adjust pricing.
How It Works
Streamlined processing for startups and mature corporations alike.
Data Submission
Upload your corporate financial statements (P&L, Balance Sheet) and previous tax returns.
Tax Planning
Our CPAs analyze your books to maximize deductions and determine precise tax liabilities.
Form Drafting
We generate Form 1120, alongside Schedules L, M-1, and M-2 accurately reflecting corporate equity.
Review & Sign
Corporate officers review the draft returns and digitally sign the e-file authorization form (8879-CORP).
IRS Acceptance
We transmit the data to the IRS and deliver the formal acceptance confirmation for your corporate records.
Specialized Compliance
Ensuring C-Corps survive rigorous IRS audits.
Shareholder Loans
Loans between the C-Corp and shareholders must be treated strictly with formal notes and interest. We analyze these to prevent the IRS reclassifying them as taxable dividends.
Stock & Equity
Tracking common stock, preferred stock, and Additional Paid-in Capital (APIC) correctly on the balance sheet is vital for startups raising venture capital.
Tax Credits
We help identify eligible R&D tax credits and other incentives that can directly offset the 21% corporate tax liability or payroll taxes.
Frequently Asked Questions
Form 1120 must be filed by all domestic C-Corporations, as well as LLCs that have elected to be taxed as C-Corporations. If your company is incorporated as a C-Corp (like most Delaware startups), you must file this return regardless of revenue.
For calendar year corporations, the filing deadline is April 15th. If the corporation uses a fiscal year, the return is due by the 15th day of the 4th month after the end of its tax year. A 6-month extension can be requested via Form 7004.
Currently, the US federal corporate income tax rate is a flat 21% on taxable net income. In addition, depending on the state of incorporation or physical operation, state corporate taxes may also apply.
If a C-Corporation is at least 25% owned by foreign persons, it must file Form 5472 along with Form 1120. Form 5472 reports related-party transactions and carries a $25,000 penalty if not filed accurately.
Yes. Net Operating Losses (NOLs) can generally be carried forward indefinitely to offset up to 80% of taxable income in future years, helping startups that lose money initially save on taxes when they become profitable.
Yes, if the corporation expects its tax bill to be $500 or more for the year, it must make quarterly estimated tax payments. Failure to do so can result in underpayment penalties.
We need comprehensive financial statements (Income Statement, Balance Sheet), previous year's tax return, details of any capital investments, asset purchases for depreciation, and information on foreign ownership.
Double taxation occurs in C-Corporations because the corporation is taxed on its profits (at 21%), and then the shareholders are taxed individually when those profits are distributed as dividends. Proper tax planning can mitigate this.
Yes, if your C-Corporation is registered in a state with corporate income tax (e.g., Delaware has a corporate income tax and franchise tax), you must file a state return. We can handle state filings as an add-on.
Yes. In fact, corporations with $10 million or more in total assets are required to e-file. We electronically file most corporate returns to ensure fast processing by the IRS.
Related US Compliance Services
FinCEN BOI Reporting
Mandatory federal filing detailing company ownership. Avoid $500 daily penalties.
Single-Member LLC Tax Return
For disregarded entities requiring Form 1120 pro-forma and Form 5472.
Partnership Tax Return
Multi-member LLC tax filing, including Form 1065 and K-1 generation.
READY FOR APRIL 15?
File Form 1120 Securely.
Protect Corporate Status.
Corporate taxes require precision. Ensure your C-Corp is fully compliant with the IRS to avoid massive late fees and protect shareholder equity.
CPA-Guided Preparation · Accurate Reconciliations · Secure E-Filing