
Fiduciary services for architecture firms in Onex without the stress: how it works
Delegate, digitalise or do it all yourself? Around fiduciary services in Onex, every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.
The Swiss legal frame for fiduciary services
Whether a business sits in Onex or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for fiduciary services. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
The law also settles the form: accounts may be kept in a national language or in English, on paper or electronically (art. 957a para. 5 CO). That pragmatism lets fiduciary services run entirely on digital tools — no paper binder is required.
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.
For fiduciary services, the golden rule is to discover nothing in January: every uncertainty (doubtful receivable, dispute, unsellable stock) must be identified before the closing date, not after.
A Swiss SME's accounting calendar
The typical annual cycle: monthly or quarterly AHV instalments, VAT returns (quarterly under the effective method, semi-annual under the net tax rate), the final salary declaration in January, closing in the first half-year, then the tax return and the annual VAT reconciliation. Each link depends on the quality of the previous one.
For fiduciary services, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.

Outsource fiduciary services or keep it in-house?
A good test before choosing: ask the fiduciary HOW it wants to receive the documents. A precise answer (formats, frequency, platform) says more than any brochure — including in Onex.
For fiduciary services, 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
Working with a fiduciary from Onex no longer depends on geography: the documents of a business in Onex are shared online, while the canton Geneva keeps its own deadlines for the tax return.
For a business in Onex, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Geneva.
Frequently asked questions
Do you need a fiduciary for fiduciary services, 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.
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 Onex as anywhere.
How much does fiduciary services 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.
How long must records related to fiduciary services 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.
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