Advisor handing a document and pen to a client

Sole proprietorship for engineering firms in Wettingen explained simply

Delegate, digitalise or do it all yourself? Around sole proprietorship in Wettingen, every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.

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.

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 sole proprietorship from the first month costs far less than reconstructing a whole year in December.

Swiss VAT: rates, threshold and filings

Three rates coexist in Switzerland: 8.1% for most supplies, 2.6% for everyday essentials and 3.8% for accommodation. Businesses staying under CHF 100,000 a year are exempt from registration but may opt in voluntarily — useful to reclaim input VAT on investments.

For businesses in Wettingen, VAT is in practice the most audited tax: punctual returns consistent with the books markedly reduce the odds of a deep audit of sole proprietorship.

Salaries and social contributions: the rates to know

A Swiss salary reads in three columns: gross, employee social deductions, employer contributions. Confusing them distorts cost prices — and quotes from businesses in Wettingen.

For sole proprietorship, the gap between agreed gross and paid net surprises every new employer: simulate it BEFORE hiring to avoid misunderstandings with the future employee.

Team analysing financial charts around a table

The Swiss legal frame for sole proprietorship

Whether a business sits in Wettingen or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for sole proprietorship. 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 sole proprietorship run entirely on digital tools — no paper binder is required.

Wettingen: what changes, what does not

Sole proprietorship, Sàrl or SA in Wettingen: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.

For a business in Wettingen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.

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 Wettingen too.

How long must records related to sole proprietorship 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 Wettingen can therefore archive fully digitally.

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 Wettingen 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 Wettingen.

Also worth reading

In neighbouring municipalities

Switch to accounting that keeps itself up to date

MyFiducia.ai automates sole proprietorship for businesses in Wettingen: 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.

    Sole proprietorship for engineering firms in Wettingen