Residents of Appenzell Innerrhoden (AI) are generally required to file an annual income and wealth tax return covering worldwide income and assets (subject to treaty relief and allocation rules between cantons and countries). This page explains who must file, key deadlines, how the filing process works and how the rules interact with withholding tax (Quellensteuer) for foreign nationals.

Who Must File an Income Tax Return in Appenzell Innerrhoden?

You must typically file a tax return in AI if any of the following apply:

• You are resident in Appenzell Innerrhoden at the end of the tax year.
• You move to or from the canton during the year and are resident for part of the year.
• You are self-employed or operate a business in the canton.
• You hold a permanent establishment or partnership interest in AI.
• You own real estate located in Appenzell Innerrhoden (limited tax liability).
• You are subject to withholding tax and meet the requirements for a subsequent ordinary assessment.

Married couples and registered partners who live together file a joint tax return that includes income and assets of both spouses and dependent children.

Residents vs. Non-Residents

The filing obligation depends on your tax status:

• Residents declare worldwide income and assets, with relief for foreign taxes where applicable.
• Non-residents with limited tax liability declare only income and assets taxable in AI (e.g., real estate or a permanent establishment located in the canton).

Interaction with Withholding Tax (Quellensteuer)

Foreign nationals without a permanent residence permit may be subject to withholding tax. In AI:

• Employers deduct tax at source based on the applicable tariff.
• A subsequent ordinary assessment may be required or available, for example if:
  • your income exceeds a certain threshold,
  • you have substantial additional income or assets,
  • you want to claim deductions not included in the withholding tariff.

Withholding tax paid is credited against the final tax liability and may lead to an additional payment or a refund.

Filing Deadlines

Appenzell Innerrhoden sets annual deadlines for filing tax returns. Generally:

• Tax returns are filed on a calendar-year basis.
• The ordinary filing deadline is several months after year-end.
• Deadlines may differ between individuals and legal entities.

Exact deadlines vary from year to year. Paper and electronic filings may have different due dates. Extensions are usually available upon request.

Extensions of Time

You may request an extension if you cannot file on time:

• Requests must generally be made before the original deadline.
• Extensions are granted for a limited period.
• Additional extensions may be possible for justified reasons (illness, missing documents, complex situations).

Documents and Information Required

To file your AI tax return, you may need the following (non-exhaustive):

• Salary certificates (Lohnausweise),
• Self-employment accounts and income statements,
• Bank and investment statements,
• Information on Swiss and foreign real estate,
• Proof of deductible expenses (commuting, professional expenses),
• Pension contribution statements,
• Insurance premium documentation (where deductible),
• Information on dependants,
• Details of foreign income and foreign tax paid.

Depending on your circumstances, additional documents may be required.

New Arrivals and Departures

Special rules apply if you move into or out of Appenzell Innerrhoden:

• You must declare income attributable to your period of residence or limited tax liability in the canton.
• Arrival and departure dates must be recorded accurately.
• Moves between cantons require correct allocation of income for the year.

Self-Employed Persons and Business Owners

If you are self-employed or run a business in AI, you must:

• File a tax return including business income and assets,
• Submit accounts (profit and loss statement, balance sheet),
• Pay income tax and, where applicable, capital tax on business assets.

Real Estate Owners

If you own real estate in Appenzell Innerrhoden, you must declare:

• Rental income or imputed rental value,
• Mortgage interest and property-related deductions,
• The taxable value of the property for wealth tax purposes.

Non-residents owning property in the canton are subject to limited tax liability and may need to file a return.

Consequences of Late or Non-Filing

Missing or late filings may result in:

• Reminders and administrative fees,
• Estimated assessments,
• Penalties and late interest.

Practical Considerations

In practice, many taxpayers in AI:

• Use the official cantonal tax software or online portal,
• Maintain a dedicated file for tax documents throughout the year,
• Seek professional help for cross-border or complex situations.

Filing requirements should be considered together with rates, deductions, special rules and examples to understand your full tax position.