
Everything that matters about sole proprietorship for SA companies in Salmsach
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on sole proprietorship in Salmsach: what the law requires, what can be automated, and when to delegate.
Choosing the structure: Sàrl, SA or sole proprietorship
Settling in Salmsach does not change federal law, but the canton shapes what follows: profit and capital tax rates, family allowances, possible start-up support. Comparing seriously before fixing the seat can pay off — moving a company later costs more.
On taxes, corporate profit bears direct federal tax at 8.5% (statutory rate) plus cantonal and communal tax — the total effective burden varies markedly between cantons. A realistic business plan and accounts kept from the start make bank credit noticeably easier.
Salaries and social contributions: the rates to know
Hiring the first employee triggers everything at once: affiliation to AHV and LPP funds, accident insurance, family allowances, working-time rules. A complete payroll file from day one avoids catch-ups.
Withholding tax applies to foreign employees without a C permit: the employer deducts tax at the cantonal rate and remits it. The annual salary certificate remains mandatory for all staff — it is the linchpin connecting payroll accounting, tax returns and AHV audits.
Digitalising sole proprietorship: what actually works
A serious accounting document archive links every record to its entry, timestamps versions and logs access — exactly what Swiss bookkeeping regulation expects from probative electronic retention. Chronological filing by financial year becomes an automatic by-product.
The winning pair for sole proprietorship: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.

The Swiss legal frame for sole proprietorship
A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Salmsach as anywhere.
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 sole proprietorship run entirely on digital tools — no paper binder is required.
Salmsach: what changes, what does not
Salmsach (postal code 8599, canton Thurgau) applies the same federal rules as the rest of the country: what changes in Salmsach are the cantonal counterparts — tax administration, compensation office, commercial register.
Federal deadlines do not move in Salmsach: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 8599 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 Salmsach as anywhere.
What are the current Swiss VAT rates?
Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Salmsach.
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 Salmsach too.
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 Salmsach as anywhere.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in Salmsach: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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