Sole proprietorship required documents in Solothurn without the stress: how it works
Delegate, digitalise or do it all yourself? Around sole proprietorship in Solothurn, every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.
Choosing the structure: Sàrl, SA or sole proprietorship
Partners from day one? A shareholders' agreement settles what the articles do not: exit, deadlock, valuation. Signing it while everything is fine costs an evening; negotiating it in a crisis costs the company.
Settling in Solothurn also means thinking about insurance from incorporation: professional liability, property, business interruption — the accounts keep track of them and the closing allocates them correctly.
The Swiss legal frame for sole proprietorship
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Solothurn with a clean audit trail sails through these exercises.
For sole proprietorship, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.
Swiss VAT: rates, threshold and filings
Registration happens with the Federal Tax Administration and yields a VAT number based on the business identifier (format CHE-xxx.xxx.xxx VAT). From then on, every invoice must state that number, the rate applied and the tax amount — three details sole proprietorship should lock down from day one to avoid retroactive fixes.
Also useful for sole proprietorship: some supplies are excluded from VAT (health, education, property rental) — with no corresponding input VAT right. Qualifying revenues correctly from the start avoids surprises.
Salaries and social contributions: the rates to know
Hiring the first employee triggers everything at once: affiliation to AHV and LPP funds, accident insurance, family allowances, working-time rules. A complete payroll file from day one avoids catch-ups.
An often underestimated point: self-employed status is granted by the compensation office — or not. Whoever invoices essentially one main client risks requalification as an employee, with contribution arrears charged to the principal. Clarifying AHV status before starting avoids that trap.
Solothurn: what changes, what does not
Solothurn (postal code 4500, canton Solothurn) applies the same federal rules as the rest of the country: what changes in Solothurn are the cantonal counterparts — tax administration, compensation office, commercial register.
Federal deadlines do not move in Solothurn: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 4500 changes nothing about those rules, only the sender's address.
Frequently asked questions
Can sole proprietorship be automated with AI?
Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches sole proprietorship.
What are the legal obligations for sole proprietorship in Switzerland?
The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Solothurn: federal law applies.
When must a business register for VAT?
As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Solothurn as everywhere in Switzerland.
When is entry in the commercial register mandatory?
A Sàrl and an SA only come into existence with their registration. A sole proprietorship must register from CHF 100,000 of annual revenue; below that, registration stays voluntary but adds credibility and protects the business name. Registration goes through the canton's commercial register office — for Solothurn too.
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MyFiducia.ai automates sole proprietorship for businesses in Solothurn: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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