Thurgau Capital Tax
Last updated: 14 Dec 2025
Thurgau Capital Tax — Equity Tax Rules
How capital tax works for companies in the Canton of Thurgau (TG): who is subject to equity tax, how the taxable capital base is determined (including hidden equity), how the cantonal rate and minimum tax mechanisms operate, which reliefs exist for participation-heavy structures, and how capital tax interacts with corporate income tax and compliance.
Scope & Taxpayers
- Resident companies. Capital tax applies to companies with statutory seat or effective place of management in Thurgau (AG, GmbH, cooperatives and other juristische Personen), on their equity allocable to Thurgau.
- Nonresident entities. Nonresident companies with a permanent establishment in Thurgau or Thurgau-situs real estate are subject to capital tax on the equity attributable to those Thurgau factors (allocation is key).
- Tax period and valuation date. Capital tax is assessed annually with the corporate tax return. The starting point is the balance sheet for the year, but tax-value adjustments can apply and hidden equity may be added (e.g. thin-cap recharacterisation of shareholder loans).
- Legal form. This page focuses on capital companies and cooperatives. Associations and foundations may be exempt or subject to separate rules depending on purpose.
Tax Base: Equity & Hidden Equity
For Thurgau capital tax, the taxable base is equity attributable to the canton: paid-in share capital and reserves, open and hidden, subject to adjustments and reliefs in specific situations.
| Component | Included? | Comment |
|---|---|---|
| Share/paid-in capital | Yes | Included in taxable equity for AGs and GmbHs based on registered (commercial register) capital. |
| Open reserves | Yes | Legal reserves, voluntary reserves and retained earnings form part of taxable equity. |
| Hidden reserves / goodwill | Yes, in principle | Relevant in migrations, restructurings and related-party transactions; adjustments can apply where book values diverge from tax values. |
| Revaluation / step-up reserves | Yes | Revaluations and step-up amounts recorded in equity increase the capital tax base (subject to any transitional rules). |
| Shareholder loans / hybrids | Partially | Excessive shareholder loans may be treated as hidden equity under Swiss thin-cap practice, increasing taxable equity and affecting interest deductibility. |
| Participations & certain group positions | Yes, but often relieved | Qualifying participations can be relevant for reduced-rate capital tax (and profit-tax participation relief). Coordinate both. |
For groups, allocating equity between Thurgau and other cantons or foreign jurisdictions is often the decisive technical step. Use consistent allocation keys and keep documentation aligned with the tax return schedules.
Rates, Minimum Tax & Reduced-Rate Capital
Standard rate & minimum tax
Thurgau applies a capital tax on taxable equity. As in many German-speaking cantons, the statutory “simple” rate is combined with a tax factor (Steuerfuss) to produce the effective cantonal/communal burden.
Thurgau also typically applies a minimum tax concept, ensuring a baseline tax amount for juristic persons even when profit tax is low. In equity-heavy or low-profit profiles, minimum tax can be the binding outcome and should be explicitly modelled.
For current-year effective figures (including the relevant tax factors), use:
- the hub Rates page, and
- official Thurgau corporate tax tools and guidance (where available for the current year).
Reduced-rate capital (participations) & typical relief themes
Participation-heavy structures can trigger relief mechanisms. While participation relief primarily affects profit tax, cantons often also provide capital-tax reductions (rate/base/credit) for qualifying participations and, in some cases, IP.
- Holdings. Holding-heavy entities often have low profit tax due to participation relief but still meaningful equity; capital tax and minimum tax become important.
- Financing centres. Intra-group loans can affect equity composition and thin-cap exposure (hidden equity risk).
- STAF alignment. If IP and STAF instruments are involved, coordinate profit tax relief with capital tax modelling.
For complex holding, migration or financing cases, Thurgau ruling practice can be used to confirm treatment and allocation.
Interaction with Profit Tax
Capital tax and corporate income tax are coordinated in Thurgau. Key points:
- Same return, separate bases. Profit tax is levied on taxable income; capital tax is levied on taxable equity.
- Minimum tax mechanics. Low-profit or loss-making entities can still face a baseline tax via minimum tax concepts, often linked to capital/equity.
- Equity vs. debt. More equity increases capital tax but reduces thin-cap risk; excessive shareholder debt can be reclassified as hidden equity (raising both capital tax and profit-tax adjustments).
- Participation profiles. Participation relief reduces profit tax; capital tax can remain material for equity-heavy holdings.
For profit tax, see the Thurgau corporate tax page and the calculator.
Planning Points & Typical Cases
| Theme | Capital tax angle | Typical actions |
|---|---|---|
| Financing structure | Equity increases capital tax; shareholder loans can be challenged and treated as hidden equity. | Review financing mix; document arm’s-length terms; run thin-cap checks; coordinate interest deductibility and equity exposure. |
| Holding structures | Holdings often have low profit tax (participation relief) but meaningful equity, making capital/minimum tax the binding cost. | Model minimum tax outcomes; confirm participation qualification; consider substance and allocation in Thurgau. |
| Real estate & allocation | Thurgau-situs real estate can increase the Thurgau equity allocation share and capital tax exposure. | Document valuations and allocation keys; manage financing; consider ring-fencing consistent with business substance. |
| Restructurings & migrations | Seat transfers and restructurings can trigger equity/tax-value adjustments and shift allocation keys. | Prepare pro-forma balance sheets; map tax values vs book values; seek rulings where material. |
| Low-profit years | Capital/minimum tax can become binding when profit tax is low. | Model downside years; consider legal equity/debt rebalancing; ensure documentation supports structure and substance. |
Compliance Snapshot
Capital tax is assessed and collected together with corporate income tax for juristic persons. For procedural detail, see Forms & deadlines. Key points include:
| Area | Key points |
|---|---|
| Return | Annual corporate tax return includes both profit and capital tax schedules, plus equity reconciliation and allocation schedules where needed. |
| Deadline | Deadlines follow Thurgau practice (often tied to year-end with extensions possible). Equity documentation should align with the same period. |
| Documentation | Balance sheet; equity reconciliation; participation schedules; related-party financing/thin-cap analysis; allocation keys for multi-canton/foreign elements; real estate documentation where relevant. |
| Assessment & objections | Assessments typically cover profit and capital tax. Objections should separate profit-tax base issues from equity/allocation/minimum-tax issues. |
FAQs
What is taxed under Thurgau capital tax?
Thurgau capital tax is levied on the company’s equity attributable to Thurgau: share capital, open reserves, retained earnings and, where relevant, hidden equity. For multi-canton businesses, allocation rules determine the Thurgau share of equity.
Does Thurgau apply a minimum tax?
Yes—Thurgau practice typically includes a minimum tax concept so that juristic persons contribute a baseline amount even if profit tax is low. This is especially relevant for holdings, start-ups and asset-rich companies.
How is the Thurgau capital tax rate determined?
Thurgau applies a statutory “simple” capital tax rate and then uses the applicable tax factor (Steuerfuss) to determine the effective cantonal/communal burden. Effective burdens can vary by year and commune.
How does capital tax interact with corporate income tax in Thurgau?
Profit tax and capital tax are computed on different bases but handled together in the annual return. Participation relief can reduce profit tax while capital tax (and minimum tax) can remain meaningful for equity-heavy structures.
Can capital tax be reduced through planning?
Within legal limits, yes. Typical levers include optimising equity vs. debt (without triggering thin-cap recharacterisation), managing allocation keys for multi-canton structures, and using rulings for complex holding, migration or financing cases.
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