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Bookkeeping for construction companies in Isone: what every SME should know

Bookkeeping for construction companies in Isone raises the same questions for most Swiss SME owners: which obligations apply, which deadlines are running, which documents to prepare. This page covers the federal rules in force — without unnecessary jargon.

The Swiss legal frame for bookkeeping

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. Bookkeeping sits squarely within this frame, including for companies based in Isone.

For bookkeeping, 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

A chart of accounts gets documented: one description line per account (what, when, VAT) is enough for two people to post the same way. It is the quality manual of bookkeeping, valid in Isone as anywhere.

In an SME in Isone, the chart of accounts is also a delegation tool: clear posting rules let a non-accountant prepare most entries without error.

Digitalising bookkeeping: what actually works

Automation is judged on the exceptions: what happens when the document is unreadable, the supplier unknown, the amount divergent? A good tool isolates those cases and lets a human decide fast — precious for teams in Isone.

For bookkeeping, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

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Outsource bookkeeping 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.

A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.

Isone: what changes, what does not

Working with a fiduciary from Isone no longer depends on geography: the documents of a business in Isone are shared online, while the canton Ticino keeps its own deadlines for the tax return.

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

When is entry in the commercial register mandatory?

A Sàrl and an SA only come into existence with their registration. A sole proprietorship must register from CHF 100,000 of annual revenue; below that, registration stays voluntary but adds credibility and protects the business name. Registration goes through the canton's commercial register office — for Isone too.

Does MyFiducia.ai work for a business based in Isone?

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 Isone manages its documents, VAT and exports exactly as anywhere in Switzerland.

Which documents should be prepared for the year-end closing?

Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in Isone: the CO dictates it, not the commune.

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 Isone as anywhere.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates bookkeeping for businesses in Isone: 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.

    Bookkeeping for construction companies in Isone