Form CA4
Form CA4 is a corporation tax return form issued by the Revenue Commissioners for companies in Ireland. It is used to report taxable profits and calculate corporation tax liabilities for accounting periods.
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Form CA4
Form CA4 is a corporation tax return form issued by the Revenue Commissioners for companies in Ireland. It is used to report taxable profits and calculate corporation tax liabilities for accounting periods.
Risk Radar
- The most common mistake is miscalculating taxable profits by including non-deductible expenses.
- Incorrect calculation of taxable profits
- Missing allowable deductions
- Late submission leading to penalties
- Incomplete information about business activities
Plain English
This is the main tax form for companies in Ireland. If your business is registered as a company with Revenue, you'll likely need to complete this form once a year to report your profits and pay the correct amount of corporation tax.
Submission Date
- Form CA4 must generally be filed within 9 months of the end of your company's accounting period. Late submissions may incur penalties and interest charges.
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
What this form is for
- • Use this form if your company is registered for corporation tax in Ireland
- • Complete this form annually for each accounting period
- • Use this form when reporting profits and calculating corporation tax liability
- • Use this form when claiming certain corporation tax reliefs or exemptions
- • Do not use this form for income tax returns (Form 11) or VAT returns (Form VAT 3)
Use this form or another form?
| Situation | Likely form | Why it matters | Check before you continue |
|---|---|---|---|
| Company with accounting period ending December 31 | Form CA4 | Standard annual corporation tax return | Confirm your company's tax status with Revenue |
| Newly incorporated company | Form CA1 (first return) | Initial registration and first tax return | Check if special provisions apply to your first accounting period |
| Company with losses to carry forward | Form CA4 with additional schedules | Reporting losses for future offset | Ensure proper documentation of loss calculations |
| Company claiming capital allowances | Form CA4 with capital allowances schedule | Claiming deductions for capital expenditure | Maintain detailed records of qualifying assets |
| Non-resident company with Irish operations | Form CA4 with additional declarations | Reporting Irish-sourced income | Confirm your tax residency status with Revenue |
Deadline or filing window
Form CA4 must generally be filed within 9 months of the end of your company's accounting period. Late submissions may incur penalties and interest charges.
Before you submit
- • Verify all financial figures match your company's accounts
- • Check that all required sections are completed
- • Confirm that calculations are accurate
- • Ensure all necessary supporting documents are attached
- • Check that the form is signed by an authorized person
- • Verify the company registration number is correct
- • Check that the accounting period dates are accurate
- • Ensure contact information is up to date
How to file this form
- 1Gather all financial statements and tax documentation
- 2Complete the form with accurate financial information
- 3Calculate corporation tax liability based on current rates
- 4Submit through Revenue Online Service (ROS) if possible
- 5Keep a copy of the submitted form for your records
- 6Monitor for any correspondence from Revenue
- 7Follow up if you don't receive an acknowledgment within a reasonable time
Known limitations
- • Form CA4 may not cover all types of corporation tax reliefs
- • Complex group structures may require additional forms
- • The form may not cover international tax reporting requirements
- • Certain industries may have specific reporting requirements not covered in this form
- • The form may not address recent changes in tax legislation until updated versions are released
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✦ Open in AI EditorCurrent Form Status
Form CA4 is currently the standard corporation tax return for Irish companies, though specific requirements may change with annual budgets or tax legislation updates.
Agency: Revenue Commissioners
What changed or needs a fresh check
- • Check that you're using the current version of Form CA4
- • Verify that the form includes the latest tax rates and thresholds
- • Confirm that any new corporation tax reliefs are applicable
- • Ensure that reporting requirements haven't changed
- • Check if digital filing through ROS has any new requirements
Quick Facts
Form Details
- Agency
- Revenue Commissioners
- Category
- Capital Acquisitions Tax
- Source
- CAT Forms ↗
Downloads
After you file
- • Keep a copy of the filed form and any supporting documents
- • Monitor your ROS account for any correspondence or updates
- • Set reminders for future filing deadlines
- • Review any correspondence from Revenue promptly
- • Make any necessary amendments if errors are discovered after submission
- • Keep records of all tax filings for at least 6 years
Source and verification log
- • Form CA4 is issued by the Revenue Commissioners
- • The form is used for corporation tax reporting in Ireland
- • Submissions are typically made through Revenue Online Service (ROS)
- • The standard deadline is within 9 months of the accounting period end
- • Not confirmed in official source: specific sections included in the form
- • Not confirmed in official source: current tax rates applicable to the form
- • Not confirmed in official source: penalties for late submission
- • Not confirmed in official source: recent changes to the form requirements
Common confusion points
8 things to watch for
- 1
Distinguishing between accounting profits and taxable profits
- 2
Understanding which expenses are deductible for corporation tax
- 3
Determining the correct accounting period for filing purposes
- 4
Knowing when to include capital allowances in calculations
- 5
Understanding the difference between provisional and final tax payments
- 6
Determining if corporation tax installments are required
- 7
Understanding how losses can be carried forward or back
- 8
Knowing when professional advice is needed for complex situations
Related Guides & Resources
Irish Form No. 29 Notice of the Decision or Claim of the Revenue Commissioners - No. 29 Notice of the Decision or Claim of the Revenue Commissioners
Irish COURTS form No. 29 Notice of the Decision or Claim of the Revenue Commissioners: Appendix C: Notices, Affidavits etc - Forms in Superior Court Proceedings.
View →IRS Form 23 — Application for Enrollment to Practice Before the Internal Revenue Service
IRS Form 23: Application for Enrollment to Practice Before the Internal Revenue Service
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IRS Form 1023-EZ: Streamlined Application for Recognition of Exemption Under Section 501(c)(3) of the Internal Revenue Code
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IRS Form 2553: Election by a Small Business Corporation (Under Section 1362 of the Internal Revenue Code)
View →Source transparency
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