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Accounting outsourcing for construction companies in Thônex: 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 Thônex.

The Swiss legal frame for accounting outsourcing

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.

Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For accounting outsourcing, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.

Year-end closing: how the mechanics work

Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.

The notes complete the figures: valuation principles, liabilities towards pension institutions, contingent liabilities, or the number of full-time positions. Careful notes reduce questions from the auditor and the banks.

A Swiss SME's accounting calendar

An accounting calendar only lives if it is shared: owner, in-house bookkeeper and fiduciary must see the same deadlines and the same status — the rule holds for every SME in Thônex.

Delays rarely come alone: neglected bookkeeping postpones the closing, hence the tax return, hence the recalculated instalments — and the business flies blind for months. Keeping the books current as you go is the only sustainable way to hold every cascading deadline.

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Outsource accounting outsourcing or keep it in-house?

Outsourcing does not exempt you from understanding: an owner who can read the balance sheet and the income statement challenges the fiduciary better — and pays for advice, not re-keying.

Changing fiduciary is not a drama: the accounting data belongs to the company, and a clean export (entries, chart of accounts, linked documents) allows a transition at year-end. A provider who locks in a client's data says a lot about how it works.

Thônex: what changes, what does not

Sole proprietorship, Sàrl or SA in Thônex: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Geneva.

Federal deadlines do not move in Thônex: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1226 changes nothing about those rules, only the sender's address.

Frequently asked questions

How much does accounting outsourcing cost in Thônex?

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.

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 Thônex: the CO dictates it, not the commune.

Do you need a fiduciary for accounting outsourcing, 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 Thônex.

Effective VAT method or net tax rate: how to choose?

The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Thônex as anywhere.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates accounting outsourcing for businesses in Thônex: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

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