Terms of Service

1. Scope, applicable law, and jurisdiction

These Terms of Service (the "Terms") govern the contractual relationship between dekla GmbH, Zürich (the "Provider") and the user (the "User") in relation to the software made available at dekla.ch (the "Software").

The contractual relationship is governed exclusively by Swiss substantive law, to the exclusion of its conflict-of-laws rules and of the United Nations Convention on Contracts for the International Sale of Goods (CISG).

The exclusive place of jurisdiction for any dispute arising out of or in connection with these Terms is Zürich, Switzerland. Mandatory places of jurisdiction, in particular the consumer forum at the consumer's domicile under Art. 32 ZPO and Art. 114 IPRG, remain reserved where applicable.

Language: for an order, the version of these Terms in the language in which you place and confirm the order applies. On acceptance, the version, language and checksum of the text shown are stored.

2. Description of the service

dekla is a client-side tool for the approximate calculation of the Swiss federal direct tax and of the cantonal, municipal, and church taxes for natural persons resident in the Canton of Zürich (as of v0.1.0; further cantons will be added in line with the published roadmap). The Software performs the calculation exclusively on the User's device.

dekla is expressly not a substitute for, and does not itself provide, individual tax or legal advice. dekla does not file the tax return with any tax authority — neither electronically nor on paper — and at no time transmits the tax data to any tax authority, fiduciary, or other third party. Filing is solely the User's responsibility.

The worksheet produced by the Software is an estimate; only the assessment decision (Veranlagungsentscheid) of the competent cantonal tax authority is binding.

3. Statutory responsibility of the User (Art. 124 and 175 DBG)

The User remains solely and personally responsible for the completeness and accuracy of the tax return (Art. 124 DBG; § 133 StG ZH). Breach of procedural duties and attempted or completed tax evasion may be sanctioned under Art. 174 ff. DBG and § 234 ff. StG ZH; this responsibility is personal and cannot be shifted to the Provider.

The User undertakes to verify the result produced by the Software, prior to filing, against the official tax calculator of the competent canton (for the Canton of Zürich: ZHprivateTax, available at www.zh.ch/de/steuern-finanzen.html) or against the binding tariffs under DBG and the cantonal tax act. Any discrepancies must be examined before filing.

The User keeps the supporting documents underlying the tax return for as long as the tax authority can ask for them (up to ten years in additional-tax proceedings); self-employed persons and legal entities must keep their accounting records and documents for ten years under Art. 126 para. 3 DBG. Discharge of these obligations lies wholly with the User; within the free functions the Provider does not retain any supporting documents on its own systems.

4. Liability

(a) Liability of the Provider for slight negligence (leichte Fahrlässigkeit) is excluded to the maximum extent permitted by Art. 100 para. 2 CO and Art. 8 UWG.

(b) Liability for gross negligence (grobe Fahrlässigkeit) and intent (Vorsatz) cannot be excluded in advance under Art. 100 para. 1 CO and remains in force as provided by law.

(c) Where liability for slight negligence is not validly excluded, it is capped per claim at the highest of (i) twelve (12) times the fees paid by the User to the Provider in the twelve months preceding the event giving rise to the claim, (ii) the price of the order concerned, and (iii) CHF 500 (minimum floor), and at an aggregate cap per User of CHF 10'000 across all claims arising in a single calendar year. This cap applies to slight negligence only, not to intent or gross negligence.

(d) Liability for indirect or consequential damages (mittelbarer und Folgeschaden), loss of profit, loss of data beyond the User's own export, and tax fines (personal sanctions) imposed on the User is excluded to the extent permitted by law. Default interest and surcharges that result from a calculation error for which the Provider is responsible are recoverable within the limit of paragraph (c); the tax lawfully owed is not itself a damage.

(e) The statutory limitation periods apply; these Terms do not change them.

(f) Nothing in this clause limits liability for personal injury, fraud (Arglist), or any liability that, under mandatory Swiss law, cannot be limited; where any individual provision conflicts with mandatory law, the legally permissible measure shall apply in lieu of the invalid provision.

5. No financial, tax, or legal advice

dekla provides neither financial services within the meaning of the Swiss Financial Services Act (FinSA / FIDLEG, SR 950.1) nor tax or legal advice within the meaning of cantonal lawyer-regulation statutes or of the fiduciary profession. In particular, the Software does not constitute investment advice, portfolio management, or a recommendation to acquire or dispose of any specific financial instrument.

Future AI-assisted hints (from Phase 5 onwards) will be configured against a versioned, red-team-tested deny list so that no specific banks, pillar-3a providers, insurers, brokers, or individual financial products are named. Generic tax categories (e.g. "pillar 3a", "professional expense allowance") remain explainable.

For individual advice, please consult a regulated financial-service provider, a qualified tax expert (dipl. Steuerexperte), a fiduciary with federal certificate, or a lawyer registered on the cantonal bar register.

6. Hints from optional AI features (Phases 5 and 6)

Once the optional "BYOK" (Bring Your Own Key, Phase 5) and "in-browser language model" (Phase 6) features become available, they will be provided on separate origins (app-byok.dekla.ch and models.dekla.ch) and will require explicit, granular consent under Art. 17 revFADP before each activation.

All output of these AI features will be marked with a persistent, non-dismissible label reading "KI-Hinweis — keine Steuer- oder Rechtsberatung. Vor Einreichung verifizieren." AI output is generative text and may be factually inaccurate; it does not replace the User's review of the worksheet or the User's responsibility under Sec. 3.

7. Territorial scope

The Software is directed at persons with tax residence in Switzerland. Paid packages are sold only to persons who declare when ordering that they are subject to Swiss tax; the declaration is stored together with the version of these Terms. Card country and nationality are not criteria. The free functions are open to everyone. No targeting of other markets is intended. To the extent that persons outside Switzerland (in particular within the European Union) nevertheless access the Software, they do so on their own responsibility; the Provider gives no assurance as to the suitability or compliance of the Software with foreign tax law. A representative within the meaning of Art. 27 GDPR is being appointed in accordance with Sec. 11 of the Privacy Notice.

8. User data on the device

Tax data and supporting documents entered into the Software remain encrypted on the User's device (see Sec. 2 and 7 of the Privacy Notice). The Provider has no access to them at any time.

The User is solely responsible for (i) the secure custody of the vault passphrase, (ii) the regular creation of vault exports (`.swisstax-vault`) and their safe storage in a separate, secure location, and (iii) keeping your documents for as long as the tax authority can ask for them and, if you are self-employed or a legal entity, for ten years (Art. 126 para. 3 DBG). In the event of loss of the passphrase together with all devices and backups, the data is irrevocably and irrecoverably lost; recovery by the Provider is technically impossible.

9. Changes to these Terms

The Provider reserves the right to amend these Terms. Material changes will be published in the Software (banner on the home page) and at dekla.ch/terms at least 30 days before they take effect. For existing orders, the terms at the time of the order apply. Changes apply to new orders and to use of the free functions from the date they take effect. Anyone who does not agree with a change can stop using the Software.

10. Severability and final provisions

Should any provision of these Terms be or become wholly or partially invalid, void, or unenforceable, the validity of the remaining provisions shall not be affected. The invalid, void, or unenforceable provision shall be deemed replaced by the valid, effective, and enforceable provision that comes closest to the economic and legal purpose of the original provision; the same applies to any gaps in the contract.

These Terms together with the Privacy Notice constitute the entire agreement between the Provider and the User concerning the Software. There are no oral side agreements. Any assignment by the User of rights or obligations arising under this agreement to a third party requires the prior written consent of the Provider.