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Social security contributions for tradespeople in Onex: the practical guide

Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on social security contributions in Onex: what the law requires, what can be automated, and when to delegate.

The Swiss legal frame for social security contributions

Swiss accounting law has been unified in the Code of Obligations since 2013: the same bookkeeping rules (art. 957a CO) and retention rules (art. 958f CO — 10 years for books, vouchers and reports) apply regardless of legal form. Social security contributions sits squarely within this frame, including for companies based in Onex.

Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.

A Swiss SME's accounting calendar

Tax instalments are steered: too low, they set up a salty final bill; too high, they tie up cash. Adjusting them on current figures is a profitable reflex, in Onex as anywhere.

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.

Digitalising social security contributions: what actually works

Artificial intelligence has changed the economics of social security contributions: automatic invoice reading reaches recognition rates that make manual entry marginal, and posting suggestions learn from corrections. The accountant does not disappear — the job shifts from data entry to control and advice.

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.

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Outsource social security contributions or keep it in-house?

The Swiss fiduciary market is dense and governed by professional practice: industry standards, business secrecy, civil liability. Compare offers on three concrete criteria — exact scope (data entry? closing? payroll? VAT?), a named contact person, and the tools used. It prevents year-end misunderstandings.

For social security contributions, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.

Onex: what changes, what does not

Onex (postal code 1213, canton Geneva) applies the same federal rules as the rest of the country: what changes in Onex are the cantonal counterparts — tax administration, compensation office, commercial register.

Onex requires no special bookkeeping: the Code of Obligations applies at postal code 1213 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

Do you need a fiduciary for social security contributions, 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 Onex.

How long must records related to social security contributions 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 Onex can therefore archive fully digitally.

What is simplified bookkeeping and who can use it?

Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Onex.

How much does social security contributions cost in Onex?

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.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates social security contributions for businesses in Onex: 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.

    Social security contributions for tradespeople in Onex