
Balance sheet preparation common mistakes in Cossonay: rules, deadlines, best practice
Whether you run a Sàrl, an SA or a sole proprietorship in Cossonay, balance sheet preparation eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Year-end closing: how the mechanics work
The CO's accounting principles frame the closing: regularity, prudence and consistency of presentation (art. 958c CO), on the going-concern assumption (art. 958a CO). In practice, that means valuation methods kept constant from one year to the next — and documented whenever they change.
A well-ordered closing file speeds everything up: bank statements at the closing date, a signed inventory, final AHV/LPP/accident settlements, new or amended contracts, and support for the accruals. Balance sheet preparation in Cossonay then finishes in days, not weeks.
Outsource balance sheet preparation or keep it in-house?
A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of balance sheet preparation lowers fees more surely than any negotiation.
For balance sheet preparation, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
The Swiss legal frame for balance sheet preparation
In Switzerland, the duty to keep accounts stems from art. 957 ff. of the Code of Obligations. Legal entities (Sàrl, SA) and sole proprietorships with at least CHF 500,000 in revenue keep full accounts: balance sheet, income statement and notes. Below that threshold, a simplified record of income, expenses and assets is sufficient.
The good news: the Swiss frame is stable and predictable. Structure balance sheet preparation once — chart of accounts, document flow, calendar — and the same organisation pays off for years.

A well-structured SME chart of accounts
The same chart serves three readings: accounting (accuracy), tax (accepted adjustments) and management (margins by activity). Modern software produces all three views without double entry.
In an SME in Cossonay, the chart of accounts is also a delegation tool: clear posting rules let a non-accountant prepare most entries without error.
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.
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
What are the current Swiss VAT rates?
Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Cossonay.
How long must records related to balance sheet preparation 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.
What are the legal obligations for balance sheet preparation 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.
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