SA incorporation for architecture firms in Lommis: rules, deadlines, best practice
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on SA incorporation in Lommis: what the law requires, what can be automated, and when to delegate.
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).
From day one, three administrative tracks open: affiliation to an AHV compensation office, review of VAT liability (CHF 100,000 threshold) and setting up the accounts. Handling SA incorporation from the first month costs far less than reconstructing a whole year in December.
Digitalising SA incorporation: what actually works
Accounting digitalisation always follows the same path: capture documents at the source (photo or PDF upload), let automatic recognition extract supplier, amount, date and VAT, approve the proposed entries, then archive each document linked to its entry. Every step removes a re-keying — and therefore an error source.
For an owner in Lommis, a dashboard only has value if the data is fresh: automating data entry means, first of all, buying up-to-date information about your own business.
The Swiss legal frame for SA incorporation
Whether a business sits in Lommis or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for SA incorporation. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
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 SA incorporation run entirely on digital tools — no paper binder is required.
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.
An often underestimated point: self-employed status is granted by the compensation office — or not. Whoever invoices essentially one main client risks requalification as an employee, with contribution arrears charged to the principal. Clarifying AHV status before starting avoids that trap.
Lommis: what changes, what does not
Working with a fiduciary from Lommis no longer depends on geography: the documents of a business in Lommis are shared online, while the canton Thurgau keeps its own deadlines for the tax return.
Lommis requires no special bookkeeping: the Code of Obligations applies at postal code 9506 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Lommis 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 Lommis as anywhere.
How long must records related to SA incorporation 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 Lommis can therefore archive fully digitally.
Does MyFiducia.ai work for a business based in Lommis?
Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Lommis manages its documents, VAT and exports exactly as anywhere in Switzerland.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates SA incorporation for businesses in Lommis: 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.