
Online accounting for plumbers in Wengi: the practical guide
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Wengi.
Digitalising online 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 — precious for teams in Wengi.
Electronic archiving is fully recognised: Swiss bookkeeping regulation admits electronic retention of records provided integrity and readability are guaranteed for the 10 years of art. 958f CO. A paper binder is no longer an obligation — provided the archiving system is serious.
The Swiss legal frame for online 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, including for a company based in Wengi.
One simple principle drives online 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.
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.
Standard numbering also enables automation: stable posting rules (same supplier, same account) make data entry predictable and the audit faster. Avoid changing the chart of accounts mid-year — migrate at the closing date, with a documented mapping table.

QR-bills and friction-free collections
The QR-bill is generated from the accounts, not the other way round: the document is born with its reference, amount and due date already linked to the receivable entry — a clear win for SMEs in Wengi.
A business in Wengi can collect by QR-bill even without sophisticated software: what matters is that every incoming payment finds its invoice, manually or automatically.
Wengi: what changes, what does not
Sole proprietorship, Sàrl or SA in Wengi: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Bern.
For a business in Wengi, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Bern.
Frequently asked questions
What are the legal obligations for online 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 Wengi: federal law applies.
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 Wengi: the CO dictates it, not the commune.
Do you need a fiduciary for online 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. With a shared platform, the fiduciary does not even need to be in Wengi.
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 Wengi as anywhere.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates online accounting for businesses in Wengi: 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.