
Sole proprietorship for the self-employed in Trey: rules, deadlines, best practice
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on sole proprietorship in Trey: what the law requires, what can be automated, and when to delegate.
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.
Swiss VAT: rates, threshold and filings
Charging VAT is not a matter of style: the number, the correct rate, the tax amount — the tax administration checks the form as closely as the substance, including at SMEs in Trey.
For businesses in Trey, VAT is in practice the most audited tax: punctual returns consistent with the books markedly reduce the odds of a deep audit of sole proprietorship.
Digitalising sole proprietorship: what actually works
Automation is judged on the exceptions: what happens when the document is unreadable, the supplier unknown, the amount divergent? A good tool isolates those cases and lets a human decide fast — precious for teams in Trey.
For an owner in Trey, 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.

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 Trey with a clean audit trail sails through these exercises.
The good news: the Swiss frame is stable and predictable. Structure sole proprietorship once — chart of accounts, document flow, calendar — and the same organisation pays off for years.
Trey: what changes, what does not
Sole proprietorship, Sàrl or SA in Trey: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Vaud.
Trey requires no special bookkeeping: the Code of Obligations applies at postal code 1552 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
Which social contributions does a Swiss employer pay?
AHV/IV/APG: 5.3% employer share (the same is withheld from the employee); unemployment insurance: 1.1% each up to CHF 148,200 a year; occupational pension (LPP) by age and plan (employer at least 50%); occupational accident insurance paid by the employer; family allowances by canton. For an employer in Trey, family allowances follow the canton's rates.
What is the difference between a limited and an ordinary audit?
The ordinary audit applies to companies exceeding, for two consecutive years, two of three thresholds: CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions. Others fall under the limited audit, and those with no more than ten full-time positions on annual average can opt out with all shareholders' consent. These federal thresholds do not depend on the registered seat — in Trey as anywhere.
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.
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 Trey can therefore archive fully digitally.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in Trey: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
The application is operated in French.