Additional Income in Ireland: The Complete 2025–2026 Guide for SMEs, Directors and Individuals

Published: January 2026
Author: Amergin Consulting Ltd.
Target Audience: Business Owners, Finance Managers, and Small Business Seeking Financial Stability
Book a meeting: https://calendly.com/amergin-group_free/30min-finance-consultation

For many people in Ireland, income no longer arrives from just one predictable source. The traditional model of earning a single salary taxed entirely through PAYE is steadily disappearing. Today, directors receive dividends alongside wages, employees earn rental or investment income, founders consult on the side, SMEs hold cash on deposit, and individuals increasingly generate income through digital platforms, foreign investments or occasional professional work.

Revenue groups all of this under one broad heading: additional income.

While the phrase sounds harmless, additional income is one of the most common sources of tax errors, Revenue queries and unexpected liabilities in Ireland. Not because people are acting dishonestly, but because additional income often sits outside automated systems. It requires active understanding, conscious disclosure and proper classification all things that are easy to overlook in busy businesses and complex personal finances.

As Ireland moves into 2026, with increased data sharing, tighter reporting regimes and greater scrutiny of non-PAYE income, additional income has become an area that businesses and individuals can no longer afford to treat casually.

What Revenue Means by “Additional Income”

When Revenue refers to additional income, it is not describing something exceptional or unusual. Instead, it is referring to any income that is not fully taxed through PAYE or deducted at source as a final tax. In other words, if income does not pass cleanly through the payroll system or another fully finalised withholding mechanism, Revenue expects the taxpayer to take responsibility for declaring it.

Additional income can arise in many ordinary ways. It may come from savings or investments, from property, from professional activities carried out alongside employment, from company ownership, or from foreign sources. What unites these different streams is not their nature, but the fact that Revenue does not automatically finalise the tax position without taxpayer involvement.

This is why additional income matters. It is not that the tax rules are unusually harsh; it is that the responsibility shifts from system to individual or business.

Why Additional Income Has Become More Important in 2025–2026

The growing importance of additional income is driven by three major changes in the Irish tax landscape.

First, income itself has diversified. Modern working life involves multiple roles, hybrid arrangements, side projects, investments and digital activity. Many people earn income that does not feel like a “job” and therefore does not feel taxable, even though it is.

Second, Revenue’s visibility has expanded dramatically. International reporting standards, enhanced employer reporting, platform reporting rules and improved analytics mean Revenue often has information about income streams before the taxpayer discloses them. Additional income is no longer hidden simply because it is not paid through PAYE.

Third, small amounts add up. A little interest here, a short-term letting there, an occasional consultancy fee or dividend individually these may feel insignificant. Collectively, they can materially change a person’s or company’s tax position.

Additional income rarely causes problems because of a single mistake. Problems arise when multiple small assumptions compound over time.

The Most Common Forms of Additional Income

One of the most widespread sources of additional income is deposit interest. As interest rates have risen, individuals and businesses are earning more on savings accounts, fixed deposits and credit union balances. While DIRT may be deducted automatically on Irish accounts, this does not always mean the tax position is complete. For company accounts, foreign accounts or self-assessment filers, further disclosure is often required.

Rental income is another major category. Whether from a long-term tenancy, a short-term letting or a room in a principal residence, rental income is fully taxable and must be declared. Expenses may be deductible, but the net profit remains subject to income tax, USC and, in some cases, PRSI. Many people underestimate how quickly occasional letting activity can create formal tax obligations.

Dividend income frequently causes confusion, particularly for company directors and shareholders. While Dividend Withholding Tax may be applied, this does not always remove the need for disclosure. Dividends must still be included in personal tax returns and can interact with higher-rate tax bands and USC.

Employment-related share income has become increasingly relevant for startups and growing SMEs. Shares, options, restricted shares and growth shares can all generate taxable income or reporting obligations even where no immediate cash is received. This is one of the least intuitive areas of additional income and one of the most heavily scrutinised.

Many professionals also earn consultancy or advisory income alongside employment. Speaking engagements, project work, board roles or specialist services may feel informal, but they are taxable regardless of frequency or scale.

Foreign income is another common area of risk. Interest, dividends, rental income or employment income earned abroad must be declared in Ireland where the individual is Irish resident or ordinarily resident. Automatic exchange of information means Revenue increasingly receives this data directly.

Finally, platform and gig-economy income has expanded rapidly. Income earned through apps, marketplaces or digital services is taxable even when casual or irregular. Revenue’s reporting focus in this area continues to increase.

Why Additional Income Is So Often Misunderstood

Most errors around additional income do not stem from deliberate avoidance. They arise from assumptions that feel reasonable but are incorrect.

People often assume that if tax was deducted somewhere along the way, nothing further is required. Others assume that foreign income is outside Revenue’s reach, that small amounts do not matter, or that once-off income does not count. Many rely on the idea that “someone will tell me if I need to declare this.”

In reality, Revenue expects taxpayers to proactively understand and disclose all income streams. The system assumes knowledge, not ignorance.

Additional Income and the Tax Return

Additional income is often the factor that brings individuals into the self-assessment system.

For Form 11 filers including company directors, landlords and the self-employed additional income must be declared in full, even where tax has already been withheld. Interest, dividends, rental income, share-based income and foreign income all belong on the return.

For PAYE taxpayers filing Form 12, thresholds and exemptions may apply, but foreign income and certain investment income still require disclosure. Understanding which form applies, and why, is essential to compliance.

Additional Income and Company Directors

Company directors face particular exposure because they often have multiple income streams running in parallel. Salary, dividends, interest on loans to the company, savings interest, rental income and share-based remuneration frequently coexist. Revenue often reviews director profiles holistically, looking for consistency between declared income, company accounts and lifestyle indicators.

What feels like separate “pots” of income to a director often looks like a single integrated financial picture to Revenue.

Additional Income for SMEs and Companies

Companies also earn additional income, often without realising it carries different tax treatment. Deposit interest, rental income from surplus property, investment returns and foreign income are all taxable under corporation tax rules and must be reflected correctly in financial statements and CT1 returns.

DIRT deducted on company interest is not final. It must be reconciled and credited appropriately, and the timing difference can affect cashflow if not planned for.

Revenue’s Increasing Focus on Additional Income

Revenue focuses on additional income because it is historically where under-declaration occurs. It is less visible than payroll income and more varied in nature. Modern compliance systems now rely on data matching, third-party reporting and behavioural analysis.

Additional income often becomes the entry point for broader Revenue engagement when discrepancies arise.

Common Errors We See in Practice

Across individuals and SMEs, the same issues recur. Foreign interest is left undeclared. Rental income is omitted for short periods. Dividends are misunderstood. Share-based income is ignored because no cash was received. Records are incomplete. Disclosures are delayed until Revenue initiates contact.

Each of these errors is usually unintentional. None of them are invisible.

Voluntary Disclosure and Additional Income

Where additional income has been omitted, early voluntary disclosure can significantly reduce penalties and interest. Timing is critical. Once Revenue has initiated an enquiry, mitigation options narrow considerably.

This is an area where professional guidance often prevents a manageable issue from becoming a costly one.

How Amergin Consulting Helps Clients Manage Additional Income

At Amergin Consulting Ltd., we approach additional income as part of a wider financial ecosystem rather than a standalone problem.

For individuals and directors, we review all income streams together, identify undeclared exposure, prepare accurate Form 11 filings, manage foreign income disclosures, handle employment-related share income correctly and support voluntary disclosures where required.

For SMEs and companies, we review non-trading income, reconcile DIRT credits, ensure correct corporation tax treatment, integrate additional income into forecasting and strengthen record-keeping and audit readiness.

At a strategic level, we help clients structure income efficiently, align remuneration and dividends appropriately, manage cashflow impact and prepare for Revenue scrutiny with confidence rather than anxiety.

Additional Income and Planning for 2026

As Irish businesses and individuals plan for 2026, attention naturally focuses on payroll, VAT and corporation tax. Additional income is often overlooked  yet it is precisely where small oversights create outsized problems.

Addressing additional income proactively brings clarity. Ignoring it creates blind spots.

Conclusion: Additional Income Is Normal Uncertainty Is Not

Additional income is now a normal feature of Irish financial life. What matters is not its existence, but how it is handled.

In 2025–2026, Revenue expects full disclosure, accurate classification, timely reporting and consistent records. With the right systems and advice, additional income becomes just another managed part of your financial picture not a source of stress.

At Amergin Consulting Ltd., we help clients replace assumption with certainty and risk with structure, so additional income supports financial stability rather than undermines it.

About Amergin Consulting Ltd.

Amergin Consulting Ltd. is a Dublin-based chartered accountancy and business advisory firm serving Ireland’s SMEs and growth companies across construction, technology, professional services, and renewable energy.
We specialise in Accounting, Payroll, Taxation, and CFO Services that help businesses build stronger foundations for profit and compliance.

Need help running a year-end tax review or planning your 2026 payroll changes?
Amergin Consulting’s finance and tax team can help you identify deductions, forecast cash flow, and ensure full compliance before the year closes.
Book your 30-minute consultation: https://calendly.com/amergin-group_free/30min-finance-consultation

Disclaimer

This article is for general informational purposes only and does not constitute financial or tax advice. While every effort has been made to ensure accuracy, Budget 2026 legislation may change upon enactment of the Finance Act 2025.
Public should seek professional advice tailored to their specific circumstances before acting on any points discussed.

Sources

Revenue Commissioners — Additional Incomes
https://www.revenue.ie/en/additional-incomes/index.aspx

Revenue Commissioners — Supporting guidance on interest, dividends, rental and foreign income
https://www.revenue.ie