Accounting for startups in Cossonay: the practical guide
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Cossonay.
The Swiss legal frame for accounting
Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Cossonay.
For accounting, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.
Outsource accounting or keep it in-house?
Responsibility stays with the client: the fiduciary executes with care, but the signed accounts bind the company. Understanding what you sign is not optional.
For accounting, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
A Swiss SME's accounting calendar
January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.
For a business in Cossonay, an isolated delay can be caught up; a structural delay is paid in interest, fines and stress. The difference between the two: a system, not good intentions.
Digitalising accounting: what actually works
Digitising does not mean hoarding PDFs: without the document-entry link, a digital file is as opaque as a box of archives — true in Cossonay as everywhere.
For an SME in Cossonay, the real gain of digitalised accounting shows day to day: no paper pile at month-end, VAT prepared continuously, and an owner reading today's figures rather than last quarter's.
Cossonay: what changes, what does not
Sole proprietorship, Sàrl or SA in Cossonay: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Vaud.
For a business in Cossonay, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Vaud.
Frequently asked questions
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 Cossonay as anywhere.
Can accounting 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 accounting.
Do you need a fiduciary for accounting, 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.
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 Cossonay, family allowances follow the canton's rates.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting 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.