Residents of Basel-Landschaft are generally required to file an annual income and wealth tax return covering their worldwide income and assets (subject to treaty relief and allocation rules between cantons and countries). This page explains who must file, what deadlines apply, how the filing process works and how withholding tax (Quellensteuer) for foreign nationals interacts with ordinary assessment.

Who Must File an Income Tax Return in Basel-Landschaft?

You must file a tax return in Basel-Landschaft if any of the following apply:

• You are resident in Basel-Landschaft at the end of the tax year.
• You moved to or from Basel-Landschaft during the year and were resident for a portion of the year.
• You are self-employed or run a business in Basel-Landschaft.
• You hold a permanent establishment or partnership interest in Basel-Landschaft.
• You own real estate located in Basel-Landschaft (limited tax liability applies).
• You are subject to withholding tax but qualify for a subsequent ordinary assessment (for example because your income/assets are above certain thresholds or you want to claim deductions not covered by withholding).

If married or in a registered partnership and living together, partners typically submit a joint tax return, including income/assets of both partners and any dependants.

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 those incomes/assets taxable in Basel-Landschaft (e.g. real estate in the canton or a business established there).

Interaction with Withholding Tax (Quellensteuer)

Foreign nationals subject to withholding tax may still need or be entitled to a full assessment. In Basel-Landschaft:

• Your employer deducts withholding tax based on the applicable tariff.
• A subsequent ordinary assessment might be required or advantageous if:
  • Your total income exceeds thresholds set by the tax authorities,
  • You have significant additional income or assets,
  • You want to claim deductions not accounted for in the withholding tax calculation.

Withholding tax already paid will be credited against final tax liability; this may result in additional tax due or a refund, depending on your circumstances.

Filing Deadlines

Basel-Landschaft applies annual deadlines for tax returns. Usually:

• Returns cover each calendar year.
• The standard filing deadline is several months after year-end.
• Deadlines may differ for individuals vs. legal entities.

Exact dates may change yearly. Paper and electronic filings may also have different deadlines. Taxpayers can generally request an extension if needed.

Extensions of Time

If you cannot meet the standard deadline, you may request an extension:

• Requests should be made before the original deadline expires.
• Extensions are usually granted for a limited additional period.
• Further extensions may be possible for justified reasons (illness, missing documents, complex financial situations).

Documents and Information Required

Typically you need (non-exhaustive list):

• Salary certificates (Lohnausweise) for all employments,
• Self-employment or business income and accounts (if applicable),
• Bank and investment statements as of year-end,
• Information about real estate (owned in Switzerland or abroad),
• Evidence of deductible expenses (commuting, professional expenses, etc.),
• Pension contribution and social security statements,
• Insurance premium documentation where deductible,
• Information on dependants (children, partner),
• Details on foreign income and foreign tax paid (for treaty or unilateral relief).

Depending on your situation additional documents may be required, e.g. business records, foreign assets, cross-border employment papers, etc.

New Arrivals and Departures

Special rules apply if you move into or out of Basel-Landschaft during the year:

• If you become resident or leave the canton, you must declare income/assets relevant for the period of residence or limited liability.
• Accurately record arrival and departure dates.
• When moving to another canton or abroad, income and assets must be allocated correctly between jurisdictions.

Self-Employed Persons and Business Owners

If you are self-employed or operate a business in Basel-Landschaft:

• You must file a full tax return including business income and assets,
• Submit financial statements (profit & loss, balance sheet),
• Be subject to income tax and, where applicable, capital tax on business assets.

Real Estate Owners

If you own real estate in Basel-Landschaft:

• Declare rental income or the imputed rental value,
• Declare mortgage interest and any eligible property-related deductions,
• Report the taxable value of the property for wealth tax assessment.

Non-residents owning property in the canton may have to file under limited liability rules.

Consequences of Late or Non-Filing

Failing to file or filing late can lead to:

• Reminder notices and administrative fees,
• Estimated assessments by the tax authorities,
• Penalties or interest on overdue taxes.

Practical Considerations

Many taxpayers in Basel-Landschaft tend to:

• Use the official cantonal tax software or online portal (if available),
• Maintain a year-round file for tax-relevant documents,
• Consult a tax advisor in cross-border, foreign-income or complex asset situations.

Filing requirements should always be assessed in conjunction with the applicable rates, deductions, special rules and examples to get a full picture of your tax situation.