
Accounting for lnstallation of heating, ventilation and air-conditioning systems: what every SME should know
NOGA code 432204 · CONSTRUCTION
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on accounting: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for accounting
In Switzerland, the duty to keep accounts stems from art. 957 ff. of the Code of Obligations. Legal entities (Sàrl, SA) and sole proprietorships with at least CHF 500,000 in revenue keep full accounts: balance sheet, income statement and notes. Below that threshold, a simplified record of income, expenses and assets is sufficient.
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.
Digitalising accounting: 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.
A dashboard only has value if the data is fresh: automating data entry means, first of all, buying up-to-date information about your own business.
Outsource accounting or keep it in-house?
Responsibility stays with the client: the fiduciary executes with care, but the signed accounts bind the company. Understanding what you sign is not optional.
Changing fiduciary is not a drama: the accounting data belongs to the company, and a clean export (entries, chart of accounts, linked documents) allows a transition at year-end. A provider who locks in a client's data says a lot about how it works.

A Swiss SME's accounting calendar
Three families of deadlines shape the year: federal (VAT within 60 days, salary declaration in January), cantonal (tax return, extensions depending on the canton) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.
The useful reflex: date every obligation the moment it arises. An employee hired means AHV/LPP deadlines created; VAT registration means a filing cycle set; a closing date fixed means backward planning of the close. Well organised, the accounting calendar fills itself.
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, a few well-chosen analytical accounts (by activity, by site) beat a forest of sub-accounts nobody ever reads.
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 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).
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.
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.
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.