
Sole proprietorship step by step in Brittnau: what every SME should know
Delegate, digitalise or do it all yourself? Around sole proprietorship in Brittnau, 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
Articles and internal organisation are written to last: circle of shareholders, transfer of shares, signature rights. Templates do the job at first, but every missing clause gets renegotiated later from a weaker position.
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.
The Swiss legal frame for sole proprietorship
Whether a business sits in Brittnau 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.
Swiss VAT: rates, threshold and filings
Since 1 January 2024, Swiss VAT rates are 8.1% (standard), 2.6% (reduced — food, books, medicines) and 3.8% (accommodation). Registration becomes mandatory from CHF 100,000 of worldwide annual turnover. For sole proprietorship, step one is therefore checking the threshold and choosing the right reporting method.
Returns are filed quarterly (effective method) or twice a year (net tax rate method). Either way the rule is identical: file and pay within 60 days after the end of the period. An annual reconciliation with the accounts is required — this is where sloppy data entry gets expensive.

Salaries and social contributions: the rates to know
Family allowances are financed by the employer through a cantonal compensation fund — rates and amounts vary from canton to canton, including in Brittnau. They come on top of the federal social insurances and appear on every payslip.
A thirteenth salary, where agreed, is accrued month by month — forget it and December reveals a charge of one-twelfth of the payroll, in Brittnau as everywhere.
Brittnau: what changes, what does not
Sole proprietorship, Sàrl or SA in Brittnau: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
Brittnau requires no special bookkeeping: the Code of Obligations applies at postal code 4805 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Brittnau as everywhere in Switzerland.
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.
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 Brittnau can therefore archive fully digitally.
What is simplified bookkeeping and who can use it?
Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Brittnau.
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MyFiducia.ai automates sole proprietorship for businesses in Brittnau: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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