
Accounting for sanitary installation: what every SME should know
NOGA code 432201 · 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
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.
The good news: the Swiss frame is stable and predictable. Structure accounting once — chart of accounts, document flow, calendar — and the same organisation pays off for years.
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.
For accounting, a few well-chosen analytical accounts (by activity, by site) beat a forest of sub-accounts nobody ever reads.
Digitalising accounting: what actually works
The classic digitalisation traps are avoidable: scanning without quality control (unreadable records), stacking disconnected tools (double entry in disguise), or neglecting access rights. One single flow from document to entry, with clear roles, beats five shiny apps.
For accounting, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

Outsource accounting or keep it in-house?
The scope goes down in writing: who enters data, who approves payments, who answers the tax office, who keeps the originals. Every “we'll see” at the start becomes a December misunderstanding.
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.
A Swiss SME's accounting calendar
The typical annual cycle: monthly or quarterly AHV instalments, VAT returns (quarterly under the effective method, semi-annual under the net tax rate), the final salary declaration in January, closing in the first half-year, then the tax return and the annual VAT reconciliation. Each link depends on the quality of the previous one.
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.
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.
How long must records related to accounting be kept?
Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders.
How much does accounting cost in Switzerland?
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 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.
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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Source: NOGA 2008 nomenclature, Swiss Federal Statistical Office (FSO). A statistical nomenclature: it describes an activity and is not a commercial register entry.