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Accounting for masonry contractors in Onex: rules, deadlines, best practice

Delegate, digitalise or do it all yourself? Around accounting 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 accounting

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. Accounting sits squarely within this frame, including for companies based in Onex.

One simple principle drives accounting: every franc in or out must be explainable by a document, an entry and an account. All of Swiss accounting law fits inside that traceability requirement.

Outsource accounting or keep it in-house?

Outsourcing accounting to a fiduciary frees up time and secures compliance; keeping it in-house preserves a continuous view and costs less in fees. The best answer is often hybrid: the company captures and digitises as it goes, the fiduciary supervises, closes the books and represents the company before the authorities.

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.

A Swiss SME's accounting calendar

An accounting calendar only lives if it is shared: owner, in-house bookkeeper and fiduciary must see the same deadlines and the same status — the rule holds for every SME in Onex.

For accounting, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.

Collaborative desk with laptops and documents, top view

A well-structured SME chart of accounts

A good chart of accounts tells the story of the business: classes 1 and 2 describe what it owns and owes, class 3 what it sells, classes 4 to 6 what it consumes. Private accounts (sole proprietorships) and shareholder current accounts (Sàrl/SA) must stay spotless: they are the first thing examined in a tax audit.

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

Onex: what changes, what does not

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

Federal deadlines do not move in Onex: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1213 changes nothing about those rules, only the sender's address.

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 Onex too.

What are the legal obligations for accounting 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 Onex: federal law applies.

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

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

Can accounting be automated with AI?

Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches accounting.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates accounting for businesses in Onex: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

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