
Accounting for other construction installation: rules, deadlines, best practice
NOGA code 432902 · CONSTRUCTION
Whether you run a Sàrl, an SA or a sole proprietorship, accounting eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
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.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For accounting, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.
A Swiss SME's accounting calendar
January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.
For accounting, deadline discipline is worth real money: default interest on late VAT, AHV adjustments, tax fines. A shared deadline calendar — fed by up-to-date figures — remains the simplest safeguard.
A well-structured SME chart of accounts
The test of a good chart of accounts is a single question: can the owner find the margins in three clicks? If not, the chart serves the tax office but not the business.
For accounting, the right granularity is decisive: enough accounts to steer the business (margins by activity, expenses by nature), few enough that every entry finds its place without hesitation. The VAT accounts (input VAT, VAT due) deserve special care — they are the basis of the annual reconciliation.

Digitalising accounting: what actually works
Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.
The selection criterion for a tool is not the length of its feature list but the robustness of the daily flow: reliable bank imports, VAT computed correctly (8.1 / 2.6 / 3.8%), a complete audit trail from document to entry, and a clean export for the auditor or fiduciary. Everything else is secondary.
Outsource accounting 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.
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.
Frequently asked questions
Effective VAT method or net tax rate: how to choose?
The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again.
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.
When must a business register for VAT?
As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments.
Do you need a fiduciary for accounting, 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.
Professions in the same sector
- Development of building projects
- General construction of buildings
- General contractor work in building construction
- General building construction and civil engineering works n.e.c.
- Building maintenance and repair work
- Construction of roads and motorways
- Construction of railways and underground railways
- Construction of bridges and tunnels
- Construction of utility projects for fluids
- Construction of utility projects for electricity and telecommunications
- Construction of water projects
- Construction of other civil engineering projects n.e.c.
This guide by municipality
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting for Swiss SMEs: 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.
Source: NOGA 2008 nomenclature, Swiss Federal Statistical Office (FSO). A statistical nomenclature: it describes an activity and is not a commercial register entry.