
Everything that matters about SA incorporation for engineering firms in Affeltrangen
Whether you run a Sàrl, an SA or a sole proprietorship in Affeltrangen, SA incorporation eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Choosing the structure: Sàrl, SA or sole proprietorship
The choice of legal form turns on three axes: liability (limited to capital for Sàrl and SA, unlimited for the sole trader), taxation (economic double taxation of company profit and dividends versus direct income taxation) and pensions (the employee of their own Sàrl is subject to mandatory LPP; the self-employed insure voluntarily).
Settling in Affeltrangen also means thinking about insurance from incorporation: professional liability, property, business interruption — the accounts keep track of them and the closing allocates them correctly.
Salaries and social contributions: the rates to know
The salary certificate is an official tax document: it feeds the employee's tax return and serves as the reference in AHV and tax audits. Issued once a year, it must match payroll accounting and the declaration to the compensation office to the centime.
For SA incorporation, the gap between agreed gross and paid net surprises every new employer: simulate it BEFORE hiring to avoid misunderstandings with the future employee.
Digitalising SA incorporation: what actually works
Access for the fiduciary, the auditor and employees is set by roles: view, enter, approve, close. Well-set rights protect the data and speed up collaboration.
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.

Swiss VAT: rates, threshold and filings
A VAT return is prepared, not endured: clean VAT accounts, one code per rate and a monthly variance check make the deadline trivial — for registered businesses in Affeltrangen too.
For businesses in Affeltrangen, VAT is in practice the most audited tax: punctual returns consistent with the books markedly reduce the odds of a deep audit of SA incorporation.
Affeltrangen: what changes, what does not
Affeltrangen (postal code 9556, canton Thurgau) applies the same federal rules as the rest of the country: what changes in Affeltrangen are the cantonal counterparts — tax administration, compensation office, commercial register.
Affeltrangen requires no special bookkeeping: the Code of Obligations applies at postal code 9556 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
Can SA incorporation be automated with AI?
Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches SA incorporation.
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. The CHF 500,000 threshold is assessed the same way in Affeltrangen.
Do you need a fiduciary for SA incorporation, 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 Affeltrangen.
How much does SA incorporation cost in Affeltrangen?
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.
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MyFiducia.ai automates SA incorporation for businesses in Affeltrangen: 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.