Pen pointing at a bar chart on paper

Limited statutory audit for engineering firms in Isone: rules, deadlines, best practice

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 Isone.

Year-end closing: how the mechanics work

The CO's accounting principles frame the closing: regularity, prudence and consistency of presentation (art. 958c CO), on the going-concern assumption (art. 958a CO). In practice, that means valuation methods kept constant from one year to the next — and documented whenever they change.

A clean closing pays beyond the legal duty: it conditions the tax return, bank discussions and the company's value in a succession. Hidden reserves (accelerated depreciation, provisions) remain admissible within cantonal tax limits — document them systematically.

The Swiss legal frame for limited statutory audit

Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Isone.

For limited statutory audit, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.

A well-structured SME chart of accounts

Concretely, limited statutory audit benefits from three tiers: balance-sheet accounts (classes 1-2) kept spotless for the closing, income accounts (classes 3-6) shaped for steering, and closing accounts (class 9) reserved for year-end entries. Each tier has its rhythm and its owner.

For a business in Isone, comparability over time beats sophistication: a chart stable for five years beats a “perfect” one rebuilt every year. Banks and the tax administration read year-on-year movements first.

Meeting in a bright conference room

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 Isone.

In Isone, as everywhere, the right collaboration rhythm follows the activity: monthly for payroll and data entry, quarterly for VAT, yearly for the closing and tax advice.

Isone: what changes, what does not

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

Isone requires no special bookkeeping: the Code of Obligations applies at postal code 6810 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

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 Isone.

How much does limited statutory audit cost in Isone?

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.

What are the legal obligations for limited statutory audit in Switzerland?

The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Isone: federal law applies.

What are the current Swiss VAT rates?

Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Isone.

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Switch to accounting that keeps itself up to date

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    Limited statutory audit for engineering firms in Isone