
Sole proprietorship for law firms in Cossonay without the stress: how it works
Sole proprietorship for law firms in Cossonay rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.
Choosing the structure: Sàrl, SA or sole proprietorship
Check the company name before any enthusiasm: availability in the commercial register, internet domain, possible trademark. Renaming later costs time and trust, in Cossonay as elsewhere.
First accounting reflex for sole proprietorship: open the document numbering with the very first expense, even before registration. Founding costs are deductible — if documented.
The Swiss legal frame for sole proprietorship
Three documents summarise the health of a Swiss business: the balance sheet (what it owns), the income statement (what it earns) and the notes (what else you should know). All the work of sole proprietorship converges on those three pages, in Cossonay too.
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.
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 Cossonay.
A business in Cossonay that crosses the threshold mid-year must register without delay: retroactive registration with interest always costs more than signing up on time.

Salaries and social contributions: the rates to know
Every salary paid in Switzerland triggers joint contributions: AHV/IV/APG at 10.6% in total, i.e. 5.3% borne by the employer and 5.3% withheld from the employee; unemployment insurance at 2.2% (1.1% each) up to CHF 148,200 of annual salary. Add occupational pension (LPP credits of 7 to 18% of the coordinated salary depending on age, employer at least 50%), accident insurance (occupational accidents paid by the employer) and family allowances.
For sole proprietorship, the gap between agreed gross and paid net surprises every new employer: simulate it BEFORE hiring to avoid misunderstandings with the future employee.
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
How much does sole proprietorship cost in Cossonay?
It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.
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 Cossonay: federal law applies.
Does MyFiducia.ai work for a business based in Cossonay?
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 Cossonay manages its documents, VAT and exports exactly as anywhere in Switzerland.
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.
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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.
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