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Sole proprietorship for the self-employed in Kaiseraugst: the practical guide

Whether you run a Sàrl, an SA or a sole proprietorship in Kaiseraugst, sole proprietorship eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.

Choosing the structure: Sàrl, SA or sole proprietorship

A Sàrl requires CHF 20,000 of fully paid-in capital; an SA CHF 100,000 of which at least CHF 50,000 paid in. Both require a notarised deed and entry in the commercial register. A sole proprietorship arises from mere activity — registration only becomes mandatory from CHF 100,000 of annual revenue.

A Sàrl and an SA must also appoint an auditor, unless they opt out (no more than ten full-time positions on annual average and unanimous shareholder consent). Many young companies start without one, then appoint an auditor when growth or investors demand it.

Swiss VAT: rates, threshold and filings

The most frequent VAT mistakes are well known: the wrong rate among 8.1%, 2.6% and 3.8%, forgotten self-supplies, and a rushed annual reconciliation. Corrections are due at the latest in the return for the period containing the 180th day after the year-end — the earlier you correct, the less default interest runs.

Input VAT deduction is the flip side of VAT charged: tax paid on purchases and investments comes back through the return, receipt in hand. Rigorous entry of supplier invoices therefore translates directly into cash.

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.

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The Swiss legal frame for sole proprietorship

Whether a business sits in Kaiseraugst or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for sole proprietorship. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.

Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.

Kaiseraugst: what changes, what does not

Sole proprietorship, Sàrl or SA in Kaiseraugst: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.

Federal deadlines do not move in Kaiseraugst: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 4303 changes nothing about those rules, only the sender's address.

Frequently asked questions

Effective VAT method or net tax rate: how to choose?

The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Kaiseraugst as anywhere.

Do you need a fiduciary for sole proprietorship, or can you do it yourself?

Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Kaiseraugst.

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 Kaiseraugst: federal law applies.

What are the current Swiss VAT rates?

Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Kaiseraugst.

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    Sole proprietorship for the self-employed in Kaiseraugst