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Sole proprietorship for engineering firms in Lostorf without the stress: how it works

Whether you run a Sàrl, an SA or a sole proprietorship in Lostorf, 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.

Sole proprietorship starts on day one: founding capital, notary and register fees are the first entries. Opening a separate business bank account immediately — even for a sole proprietorship — saves hours of sorting private from business.

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 employer in Lostorf does well to fix payday on a set day of the month: funds, employees and cash flow organise around it, and sole proprietorship becomes routine instead of a sprint.

Digitalising sole proprietorship: what actually works

A serious accounting document archive links every record to its entry, timestamps versions and logs access — exactly what Swiss bookkeeping regulation expects from probative electronic retention. Chronological filing by financial year becomes an automatic by-product.

For an owner in Lostorf, a dashboard only has value if the data is fresh: automating data entry means, first of all, buying up-to-date information about your own business.

Pen pointing at a bar chart on paper

The Swiss legal frame for sole proprietorship

For an owner in Lostorf, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.

The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.

Lostorf: what changes, what does not

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

Federal deadlines do not move in Lostorf: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 4654 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 Lostorf as anywhere.

How long must records related to sole proprietorship be kept?

Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders. A business in Lostorf can therefore archive fully digitally.

What is simplified bookkeeping and who can use it?

Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Lostorf.

Does MyFiducia.ai work for a business based in Lostorf?

Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Lostorf manages its documents, VAT and exports exactly as anywhere in Switzerland.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates sole proprietorship for businesses in Lostorf: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

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    Sole proprietorship for engineering firms in Lostorf