
Bookkeeping for SA companies in Thürnen explained simply
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on bookkeeping in Thürnen: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for bookkeeping
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. Bookkeeping sits squarely within this frame, including for companies based in Thürnen.
For bookkeeping, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.
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 a business in Thürnen, the Sterchi/Käfer structure also eases benchmarking: banks and fiduciaries reason on those standard classes to situate an SME's bookkeeping.
Outsource bookkeeping or keep it in-house?
Outsourcing bookkeeping to a fiduciary frees up time and secures compliance; keeping it in-house preserves a continuous view and costs less in fees. The best answer is often hybrid: the company captures and digitises as it goes, the fiduciary supervises, closes the books and represents the company before the authorities.
A business in Thürnen is no longer limited to fiduciaries in its canton: with a shared online platform, collaboration works remotely, documents and entries visible to both sides in real time. The choice widens to all of Switzerland — competence becomes the criterion again, not the postcode.

A Swiss SME's accounting calendar
Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.
Delays rarely come alone: neglected bookkeeping postpones the closing, hence the tax return, hence the recalculated instalments — and the business flies blind for months. Keeping the books current as you go is the only sustainable way to hold every cascading deadline.
Thürnen: what changes, what does not
Working with a fiduciary from Thürnen no longer depends on geography: the documents of a business in Thürnen are shared online, while the canton Basel-Country keeps its own deadlines for the tax return.
For a business in Thürnen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Basel-Country.
Frequently asked questions
Do you need a fiduciary for bookkeeping, 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 Thürnen.
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. For an employer in Thürnen, family allowances follow the canton's rates.
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 Thürnen as anywhere.
What are the legal obligations for bookkeeping 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 Thürnen: federal law applies.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates bookkeeping for businesses in Thürnen: 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.