
Sole proprietorship for architecture firms in St. Margrethen explained simply
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 St. Margrethen: what the law requires, what can be automated, and when to delegate.
Choosing the structure: Sàrl, SA or sole proprietorship
A Sàrl requires CHF 20,000 of fully paid-in capital; an SA CHF 100,000 of which at least CHF 50,000 paid in. Both require a notarised deed and entry in the commercial register. A sole proprietorship arises from mere activity — registration only becomes mandatory from CHF 100,000 of annual revenue.
First accounting reflex for sole proprietorship: open the document numbering with the very first expense, even before registration. Founding costs are deductible — if documented.
Digitalising sole proprietorship: 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.
For an owner in St. Margrethen, 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 sole proprietorship
A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in St. Margrethen as anywhere.
The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.

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.
A thirteenth salary, where agreed, is accrued month by month — forget it and December reveals a charge of one-twelfth of the payroll, in St. Margrethen as everywhere.
St. Margrethen: what changes, what does not
St. Margrethen (postal code 9430, canton St. Gallen) applies the same federal rules as the rest of the country: what changes in St. Margrethen are the cantonal counterparts — tax administration, compensation office, commercial register.
Federal deadlines do not move in St. Margrethen: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 9430 changes nothing about those rules, only the sender's address.
Frequently asked questions
Which documents should be prepared for the year-end closing?
Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in St. Margrethen: the CO dictates it, not the commune.
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 St. Margrethen, family allowances follow the canton's rates.
Can sole proprietorship 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 sole proprietorship.
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 St. Margrethen as anywhere.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in St. Margrethen: 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.