
Sole proprietorship required documents in Sarmenstorf: what every SME should know
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 Sarmenstorf: what the law requires, what can be automated, and when to delegate.
Choosing the structure: Sàrl, SA or sole proprietorship
Partners from day one? A shareholders' agreement settles what the articles do not: exit, deadlock, valuation. Signing it while everything is fine costs an evening; negotiating it in a crisis costs the company.
A Sàrl and an SA must also appoint an auditor, unless they opt out (no more than ten full-time positions on annual average and unanimous shareholder consent). Many young companies start without one, then appoint an auditor when growth or investors demand it.
Salaries and social contributions: the rates to know
Two of these contributions are set by law: AHV/IV/APG at 5.3% and unemployment at 1.1%, both payable by the employer. The others — LPP, accident insurance, possibly daily sickness benefits and family allowances — depend on the insurer, the industry and the pension plan. The total surcharge usually falls between 12 and 20% of gross pay, and employee deductions between 10 and 15%: these are orders of magnitude, not statutory rates.
A thirteenth salary, where agreed, is accrued month by month — forget it and December reveals a charge of one-twelfth of the payroll, in Sarmenstorf as everywhere.
Digitalising sole proprietorship: what actually works
Digitising does not mean hoarding PDFs: without the document-entry link, a digital file is as opaque as a box of archives — true in Sarmenstorf as everywhere.
For an owner in Sarmenstorf, 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
For an owner in Sarmenstorf, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.
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.
Sarmenstorf: what changes, what does not
Sarmenstorf (postal code 5614, canton Aargau) applies the same federal rules as the rest of the country: what changes in Sarmenstorf are the cantonal counterparts — tax administration, compensation office, commercial register.
For a business in Sarmenstorf, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
Frequently asked questions
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 Sarmenstorf.
When must a business register for VAT?
As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Sarmenstorf as everywhere in Switzerland.
Do you need a fiduciary for sole proprietorship, 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 Sarmenstorf.
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 Sarmenstorf too.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in Sarmenstorf: 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.