
Association accounting legal obligations in Lengwil: what every SME should know
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 Lengwil.
The Swiss legal frame for association 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.
The law also settles the form: accounts may be kept in a national language or in English, on paper or electronically (art. 957a para. 5 CO). That pragmatism lets association accounting run entirely on digital tools — no paper binder is required.
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, including in Lengwil) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.
For association accounting, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.
A well-structured SME chart of accounts
Nearly all Swiss SMEs rely on the standard SME chart of accounts (Sterchi/Käfer): classes 1 (assets) to 9 (closing), with revenue in class 3 and expenses in classes 4 to 6. Using this standard structure makes conversations with your fiduciary, auditor and tax administration far easier.
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.

Digitalising association 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.
Lengwil: what changes, what does not
Working with a fiduciary from Lengwil no longer depends on geography: the documents of a business in Lengwil are shared online, while the canton Thurgau keeps its own deadlines for the tax return.
Federal deadlines do not move in Lengwil: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 8574 changes nothing about those rules, only the sender's address.
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. The choice rests on the company's own figures, in Lengwil as anywhere.
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 Lengwil as anywhere.
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 Lengwil too.
How long must records related to association 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. A business in Lengwil can therefore archive fully digitally.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates association accounting for businesses in Lengwil: 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.