
Tax advisory for construction companies in Versoix: rules, deadlines, best practice
Delegate, digitalise or do it all yourself? Around tax advisory in Versoix, 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 tax advisory
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. Tax advisory sits squarely within this frame, including for companies based in Versoix.
The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.
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 Versoix as anywhere.
For tax advisory, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.
Swiss VAT: rates, threshold and filings
Registration happens with the Federal Tax Administration and yields a VAT number based on the business identifier (format CHE-xxx.xxx.xxx VAT). From then on, every invoice must state that number, the rate applied and the tax amount — three details tax advisory should lock down from day one to avoid retroactive fixes.
The net tax rate method simplifies life for small structures: one flat industry rate applied to turnover, with semi-annual filing. In exchange, input VAT is not deducted separately. The effective-versus-flat-rate choice should be reviewed periodically against the cost structure.

Year-end closing: how the mechanics work
The closing turns day-to-day bookkeeping into annual accounts: balance sheet, income statement and notes (art. 958 CO). Mandatory stops: accruals and deferrals, depreciation, commercially justified provisions, inventory of stock and work in progress, then VAT and AHV reconciliations.
The timetable is tight: accounts drawn up and approved by the general meeting within six months of the year-end. For tax advisory, chasing missing documents from January (bank statements, contracts, insurance settlements) avoids the last-minute sprint and auditor reservations.
Versoix: what changes, what does not
Working with a fiduciary from Versoix no longer depends on geography: the documents of a business in Versoix are shared online, while the canton Geneva keeps its own deadlines for the tax return.
Federal deadlines do not move in Versoix: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1290 changes nothing about those rules, only the sender's address.
Frequently asked questions
How long must records related to tax advisory 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 Versoix can therefore archive fully digitally.
How much does tax advisory cost in Versoix?
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 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 Versoix, family allowances follow the canton's rates.
Do you need a fiduciary for tax advisory, 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 Versoix.
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