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Interactive Corporation Tax Guide

Explore different aspects of Irish corporation tax with detailed breakdowns.

Irish Corporation Tax Rates (2025)

Trading Income

12.5%

Active business trading profits

Passive Income

25%

Investment income, rental income (excluding property trading)

Capital Gains

33%

Gains on disposal of assets

Close Company Surcharge

20%

Undistributed investment income

Corporation Tax Calculation Example

See how corporation tax is calculated for a typical Irish company.

Example Company Calculation

Company Profile

  • • Software development company
  • • Annual trading profits: €500,000
  • • Property rental income: €50,000
  • • Capital gain on asset sale: €100,000
Trading Profits @ 12.5%:€500,000 × 12.5% = €62,500
Rental Income @ 25%:€50,000 × 25% = €12,500
Capital Gains @ 33%:€100,000 × 33% = €33,000
Total Corporation Tax:€108,000

Effective Rate: €108,000 ÷ €650,000 = 16.6% overall (The low 12.5% rate on trading income keeps the overall rate competitive)

Corporation Tax Filing Requirements

Key obligations and deadlines for Irish companies.

Annual Obligations

Form CT1 Return

  • • Due 9 months after year end
  • • Must be filed even if no tax due
  • • Include audited accounts
  • • Submit via ROS online

Annual Return of Accounting Period

  • • Due 9 months after year end
  • • Filed alongside CT1
  • • Details company activities
  • • Mandatory for all companies

CRO Annual Return

  • • Due by annual return date
  • • Filed with Companies Registration Office
  • • Include audited financial statements
  • • Penalties for late filing

Payment Requirements

Small Companies (Turnover ≤€3m)

  • • Pay in full 9 months after year end
  • • No preliminary tax required
  • • Late payment interest: 0.0274% per day
  • • Automatic entitlement

Large Companies (Turnover >€3m)

  • • Pay in full 6 months after year end
  • • Preliminary tax due in month 6
  • • Must pay 90% of current year liability
  • • Higher penalties for late payment

Payment Methods

  • • ROS online payment
  • • Bank transfer to Revenue
  • • Direct debit arrangement
  • • Standing order for installments

Corporation Tax Planning Strategies

Legal strategies to optimize your company's tax position.

Key Planning Areas

1

Timing of Income & Expenses

Accelerate deductible expenses and defer taxable income where possible to optimize cash flow.

2

Capital Allowances Optimization

Maximize capital allowances on plant, machinery, and equipment purchases to reduce taxable profits.

3

R&D Tax Credits

Claim 25% R&D tax credits for qualifying research and development expenditure.

4

Pension Contributions

Corporate pension contributions are fully deductible and provide valuable employee benefits.

5

Loss Relief Planning

Utilize trading losses effectively through carry forward or group relief arrangements.

Common Corporation Tax Compliance Issues

Avoid these common mistakes that can lead to penalties and interest.

Filing Errors

×Late filing of CT1 returns
×Incorrect income classification
×Missing supporting documentation
×Failure to file nil returns

Payment Mistakes

×Late payment penalties
×Insufficient preliminary tax
×Missing payment deadlines
×Incorrect ROS payments

Best Practice Recommendations

  • Set up calendar reminders for all filing deadlines
  • Use professional accounting software for accuracy
  • Engage qualified accountants for complex matters
  • Keep detailed records and supporting documentation

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