
Everything that matters about limited statutory audit for engineering firms in Oppens
Limited statutory audit for engineering firms in Oppens rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.
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 timetable is tight: accounts drawn up and approved by the general meeting within six months of the year-end. For limited statutory audit, chasing missing documents from January (bank statements, contracts, insurance settlements) avoids the last-minute sprint and auditor reservations.
Outsource limited statutory audit 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 Oppens.
A business in Oppens can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — limited statutory audit splits very well.
The Swiss legal frame for limited statutory audit
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. Limited statutory audit sits squarely within this frame, including for companies based in Oppens.
The good news: the Swiss frame is stable and predictable. Structure limited statutory audit once — chart of accounts, document flow, calendar — and the same organisation pays off for years.

A well-structured SME chart of accounts
Shareholder current accounts demand strict hygiene: every private withdrawal documented, interest at the rates accepted by the tax administration, and a clean-up at closing.
In an SME in Oppens, the chart of accounts is also a delegation tool: clear posting rules let a non-accountant prepare most entries without error.
Oppens: what changes, what does not
Sole proprietorship, Sàrl or SA in Oppens: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Vaud.
Federal deadlines do not move in Oppens: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1047 changes nothing about those rules, only the sender's address.
Frequently asked questions
Does MyFiducia.ai work for a business based in Oppens?
Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Oppens manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Oppens.
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 Oppens, family allowances follow the canton's rates.
How long must records related to limited statutory audit 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 Oppens can therefore archive fully digitally.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates limited statutory audit for businesses in Oppens: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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