
Sole proprietorship for garages in Cossonay: what every SME should know
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 Cossonay: what the law requires, what can be automated, and when to delegate.
Choosing the structure: Sàrl, SA or sole proprietorship
The choice of legal form turns on three axes: liability (limited to capital for Sàrl and SA, unlimited for the sole trader), taxation (economic double taxation of company profit and dividends versus direct income taxation) and pensions (the employee of their own Sàrl is subject to mandatory LPP; the self-employed insure voluntarily).
Settling in Cossonay also means thinking about insurance from incorporation: professional liability, property, business interruption — the accounts keep track of them and the closing allocates them correctly.
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.
The selection criterion for a tool is not the length of its feature list but the robustness of the daily flow: reliable bank imports, VAT computed correctly (8.1 / 2.6 / 3.8%), a complete audit trail from document to entry, and a clean export for the auditor or fiduciary. Everything else is secondary.
The Swiss legal frame for sole proprietorship
Whether a business sits in Cossonay 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.
Also worth knowing: accounts may be drawn up in the currency most relevant to the business; if that is not the franc, values must additionally be stated in CHF (art. 958d para. 3 CO). Internationally active companies gain books that match their economic reality.

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.
Returns are filed quarterly (effective method) or twice a year (net tax rate method). Either way the rule is identical: file and pay within 60 days after the end of the period. An annual reconciliation with the accounts is required — this is where sloppy data entry gets expensive.
Cossonay: what changes, what does not
Working with a fiduciary from Cossonay no longer depends on geography: the documents of a business in Cossonay are shared online, while the canton Vaud keeps its own deadlines for the tax return.
Cossonay requires no special bookkeeping: the Code of Obligations applies at postal code 1304 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
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.
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 Cossonay.
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 Cossonay can therefore archive fully digitally.
Which documents should be prepared for the year-end closing?
Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in Cossonay: the CO dictates it, not the commune.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in Cossonay: 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.