Thurgau Corporate Income Tax
Last updated: 13 Dec 2025
Thurgau Corporate Income Tax — Profit Tax Rules
How corporate income tax works in the Canton of Thurgau: who is subject to profit tax, how the tax base is derived from accounting profit, how the 2.5% cantonal profit tax interacts with municipal tax factors and Swiss federal corporate income tax, and what to know about participation relief, STAF instruments, loss carryforwards and permanent establishments.
Scope & Taxpayers
- Resident companies. Companies with statutory seat or effective place of management in Thurgau are subject to unlimited tax liability on their worldwide income, with relief for foreign permanent establishments and foreign real estate under double tax treaties and intercantonal allocation rules.
- Nonresident entities. Nonresident companies are limited tax liable in Thurgau if they have a local business operation, permanent establishment or Thurgau-situs real estate. Only the profits attributable to the Thurgau nexus are taxed.
- Juristic persons only. The corporate income tax described here applies to juristische Personen (AG, GmbH, cooperative, certain foundations and associations). Partnerships and sole proprietors are taxed at owner level under personal income tax.
- Tax period. The profit tax period generally follows the financial year. A change of year-end or an extended first business year must be coordinated with the Thurgau tax administration.
- Legal form & status. The 2.5% cantonal profit tax rate applies to juristic persons as defined in cantonal law. Within this, Thurgau distinguishes between standard operating companies, holding/asset-focused structures and non-profit entities mainly via participation relief, capital-tax rules and specific exemptions rather than via legacy status-company regimes.
Tax Base: From Accounting Profit to Taxable Profit
Thurgau corporate income tax is levied on the company’s taxable net profit. The starting point is the statutory financial statements (usually Swiss CO / Swiss GAAP), with tax adjustments made under Thurgau tax law and the federal framework.
| Step | Description | Typical adjustments |
|---|---|---|
| 1. Accounting profit | Profit after tax per statutory financial statements for the relevant business year. | Profit as approved by the shareholders’ meeting, before appropriation of retained earnings and distributions. |
| 2. Add-backs | Non-deductible or partially deductible expenses are added back to profit to reach the tax base. | Hidden profit distributions; excessive interest or royalties to related parties; non-business expenses; fines and penalties; corporate income and capital tax where non-deductible; provisions that are not accepted for tax purposes. |
| 3. Deductions | Items that are tax-deductible but not (fully) expensed in the income statement can be deducted, subject to limits. | Tax-approved depreciation where higher than accounting depreciation; specific provisions; participation relief; patent-box reductions; the 130% R&D additional deduction on qualifying Swiss R&D costs; step-up and transitional relief in status-change or relocation cases. |
| 4. Allocation & exemptions | Profits allocable to other cantons or foreign permanent establishments can be exempt or taxed elsewhere under intercantonal and treaty rules. | Intercantonal allocation keys (e.g. payroll, assets, turnover); separate determination of foreign PE income; relief under double tax treaties (exemption or credit methods). |
| 5. Taxable profit | Result after adjustments and allocation, before loss offsets and special reliefs. | Loss carryforwards from the previous seven business years can be offset against current-year taxable profit. There is no loss carryback. Losses are tracked tax-wise even where, in a given year, only minimal or capital tax is effectively paid. |
The Thurgau Steuergesetz and the cantonal Steuerpraxis specify the profit definition, deductible expenses and seven-year loss carryforwards for juristic persons. In practice, the tax authorities expect a clear reconciliation from accounting profit to taxable profit as part of the corporate tax return.
Rates & Effective Burden
Cantonal & communal profit tax
Thurgau applies a cantonal profit tax on net income for juristic persons at a simple rate of 2.5% of taxable profit (statutory rate since 2020). This simple cantonal tax is then multiplied by the cantonal tax factor and by the relevant municipal tax multiplier (Steuerfuss) to determine the combined cantonal/communal profit tax burden.
Municipal multipliers differ across Thurgau’s communes. As a result, the effective cantonal/communal profit tax component for the same level of taxable profit can vary depending on the company’s location within the canton. Economic promotion materials and independent surveys typically place Thurgau among the more competitive cantons for corporate taxation.
For up-to-date Thurgau profit and capital tax parameters and examples by municipality, see the Thurgau rates page and the official Thurgau company tax calculator .
Federal corporate income tax & combined rate
In addition to cantonal/communal profit tax, companies in Thurgau pay Swiss direct federal corporate income tax at a flat rate of 8.5% on profit after tax. Because federal tax is deductible in its own tax base, this corresponds to an effective rate of about 7.8% on profit before tax.
Taking both layers together, external corporate tax comparisons indicate a combined effective corporate income tax burden in Thurgau of roughly around 13% on profit before tax for high-yield companies in competitive municipalities, with some variation across the canton. This puts Thurgau in the group of relatively low-tax cantons for corporate profit taxation.
The Thurgau tax calculator on this hub allows you to model combined cantonal, communal and federal profit tax for a given level of taxable profit and to compare scenarios between different municipalities.
Participation Relief & STAF Measures
Thurgau follows the federal framework for participation relief and has implemented the STAF instruments (patent box, R&D additional deduction, step-up and relief cap) in a way that combines moderate incentives with a relatively low ordinary profit tax rate.
| Mechanism | Overview | Typical planning aspects |
|---|---|---|
| Participation relief | Qualifying dividend income and capital gains from shareholdings in subsidiaries benefit from participation relief at both cantonal and federal level. Net participation income is only partially taxed based on a formula comparing participation income with total profit. | Minimum shareholding thresholds (typically ≥10% or CHF 1 million fair value); minimum holding period; treatment of write-downs and liquidation proceeds; interaction with foreign withholding tax and double tax treaties; impact on capital tax for large participations. |
| Patent box | Under Thurgau’s patent-box regime, qualifying income from patents and comparable rights can benefit from a 40% reduction at cantonal level: only 60% of the net patent income enters the cantonal profit-tax base, subject to the OECD nexus approach. | Identification of qualifying patents and comparable rights; nexus tracking of qualifying R&D costs; separation of patent-box income and expenses; coordination with foreign IP regimes; handling of box entry (recapture of prior R&D). |
| R&D additional deduction | Thurgau allows a 130% deduction for certain qualifying R&D expenditures incurred in Switzerland. In other words, eligible domestic R&D costs can be deducted at 130% of the accounting expense, reducing the cantonal profit-tax base. | Defining qualifying R&D activities and costs; distinguishing in-house vs. third-party R&D; ensuring consistent allocation in transfer-pricing and cost-sharing arrangements; documentation to support the enhanced deduction. |
| Step-up & status change | For status changes (e.g. from former holding or domiciliary status to ordinary taxation) and for inbound relocations, Thurgau provides step-up and transitional rules allowing hidden reserves and self-created goodwill to be recognised and amortised over time, sometimes with separate low-rate taxation of legacy reserves. | Identification and quantification of hidden reserves and goodwill; timing of realisation; interaction with foreign exit charges; coordination of cantonal and federal practice; impact on effective tax rate and Pillar 2 calculations. |
| Relief cap | The combined effect of patent box, R&D additional deduction and certain transitional reliefs is subject to a relief limitation of 50%: at least half of the taxable profit must remain fully taxed at ordinary rates even after all STAF measures. | Modelling total relief against the 50% cap; choosing the sequence and mix of patent-box and R&D claims; dealing with Pillar 2 minimum taxation in groups with very low effective rates in specific entities or cantons. |
For many SMEs in Thurgau, the main drivers are the ordinary 2.5% profit tax rate combined with participation relief and moderate capital tax. STAF instruments such as patent box and R&D additional deduction become especially relevant for IP- and R&D-intensive businesses and for groups with significant hidden reserves or relocation projects.
Losses, Groups & Permanent Establishments
- Loss carryforwards. Tax losses can generally be carried forward for up to seven years and offset against future taxable profits. There is no loss carryback. Special rules can limit the use of losses in the case of major ownership changes, discontinuation of business activities or certain restructurings.
- Group situation. Switzerland does not provide a broad fiscal unity or tax consolidation regime for ordinary corporate income tax. Each Thurgau entity files its own corporate tax return; group effects are managed via financing structures, transfer pricing, participation relief and, where applicable, intra-group loss transfers based on civil-law arrangements.
- Intercantonal allocation. Where a company has activities, real estate or permanent establishments in several cantons, profit and capital are allocated using recognised allocation keys and Swiss jurisprudence. Thurgau coordinates with other cantons to avoid double taxation, supported by intercantonal Steuerausscheidung rules.
- Foreign permanent establishments. Under many double tax treaties, profits attributable to foreign permanent establishments are exempt from Swiss taxation with progression, provided proper profit attribution is documented. Thurgau follows the federal framework for such exemptions.
- Restructurings. Mergers, de-mergers, asset transfers and migrations of seat can be tax-neutral if Swiss conditions are met (continuity of business, continuity of participation, carryover of hidden reserves, adequate consideration, etc.). Advance tax rulings from Thurgau and the federal authorities are common for significant corporate reorganisations.
Interaction with Capital Tax
Corporate income tax and capital tax are closely linked in Thurgau. Profit tax is levied annually on taxable income, while capital tax is levied on the company’s taxable equity. Both are determined on the same corporate tax return for juristic persons.
- Thurgau levies a simple capital tax of 0.15‰ (0.015%) on the taxable equity of capital companies and cooperatives, with a minimum capital tax of CHF 200 per year for these entities. For other juristic persons (e.g. associations, foundations), the same 0.15‰ rate applies, with equity below CHF 100 000 not subject to capital tax.
- Equity allocated to qualifying participations, patents and group loans benefits from substantial relief: only 10% of that equity is included in the capital-tax base, significantly reducing capital tax for holding, IP and intragroup financing structures.
- Profit tax is credited against capital tax. In profitable years, the 2.5% profit tax typically exceeds the capital-tax amount, so capital tax is effectively absorbed. In low-profit or loss years, capital tax (especially the CHF 200 minimum) acts as a minimum tax.
- For certain asset-heavy structures with low profits, a separate minimal tax on real estate can apply instead of profit and capital tax if it yields a higher burden for Thurgau real estate.
- For detailed capital-tax rules and further examples, see the Thurgau capital tax page and the combined tax calculator.
Compliance Snapshot
This page focuses on the substantive rules for corporate income tax in Thurgau. For procedural aspects — who files, which forms to use and which deadlines apply — see the dedicated Forms & deadlines page for this canton.
| Area | Key points |
|---|---|
| Filing | Annual corporate tax return for juristic persons, covering both profit and capital tax. Thurgau provides electronic tools and guidance for corporate tax returns (including via the federal online-services.admin.ch platform), but signed returns and financial statements remain binding. |
| Deadline | Filing deadlines are typically set several months after year-end and are communicated in the tax return package or assessment notice. Extensions are generally available on request (online or in writing), especially for representatives and complex cases. |
| Documentation | Signed financial statements; detailed profit-to-tax reconciliation; schedules for participation relief, patent box and R&D additional deduction; equity reconciliation for capital tax and relief on participations/IP/group loans; transfer-pricing documentation where material cross-border dealings exist. |
| Assessments & objections | The Thurgau tax administration issues combined assessments for cantonal, communal and federal tax. Objections must be filed within the deadlines set out in the assessment notice and should clearly specify which items relate to profit tax, capital tax or federal tax. |
FAQs
How high is the corporate income tax rate in Thurgau?
Thurgau applies a simple cantonal profit tax rate of 2.5% on taxable net profit for juristic persons. This simple tax is multiplied by the cantonal and municipal tax factors to determine the cantonal/ communal profit tax. Together with Swiss direct federal corporate income tax at 8.5% on profit after tax (about 7.8% on profit before tax), this leads to a combined effective corporate income tax burden in the low-teens (around 13% on profit before tax) for a standard company in a competitive municipality, before any special reliefs.
What is the difference between profit tax and capital tax in Thurgau?
Profit tax is charged annually on the company’s taxable income for the year. Capital tax is charged on the company’s equity (share capital, reserves, retained earnings and certain hidden equity) at a rate of 0.15‰ for capital companies and cooperatives, subject to a minimum of CHF 200 per year. Profit tax is credited against capital tax, so capital tax mainly functions as a minimum tax in low-profit or loss-making years. Equity linked to qualifying participations, patents and group loans enjoys a sharply reduced capital-tax base.
Are dividends from subsidiaries fully taxed in Thurgau?
No. Qualifying participations benefit from participation relief. Under this mechanism, net participation income (dividends and certain capital gains) is only partially taxed based on a formula comparing participation income with total profit. Where the conditions (e.g. at least 10% shareholding or CHF 1 million fair value) are met, the effective cantonal and federal tax on such income can be reduced substantially.
How are losses treated for Thurgau corporate income tax?
Tax losses can normally be carried forward for seven years and offset against future taxable profits. There is no loss carryback. In restructuring or ownership-change scenarios, specific rules may limit the use of loss carryforwards; in material cases, advance tax rulings from Thurgau are often used to secure the treatment of existing losses.
Does Thurgau offer advance tax rulings for planned structures?
Yes. Like other Swiss cantons, Thurgau offers advance tax rulings. These are commonly used for holding and financing structures, IP and R&D arrangements, relocations, application of STAF instruments (patent box, 130% R&D deduction, relief cap) and intercantonal or international profit allocation. A well-prepared ruling request can provide certainty on both profit and capital tax treatment over several years.
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