
Everything that matters about sole proprietorship for retail in Rümlang
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Rümlang.
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 sole proprietorship from the first month costs far less than reconstructing a whole year in December.
Swiss VAT: rates, threshold and filings
The most frequent VAT mistakes are well known: the wrong rate among 8.1%, 2.6% and 3.8%, forgotten self-supplies, and a rushed annual reconciliation. Corrections are due at the latest in the return for the period containing the 180th day after the year-end — the earlier you correct, the less default interest runs.
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
Every salary paid in Switzerland triggers joint contributions: AHV/IV/APG at 10.6% in total, i.e. 5.3% borne by the employer and 5.3% withheld from the employee; unemployment insurance at 2.2% (1.1% each) up to CHF 148,200 of annual salary. Add occupational pension (LPP credits of 7 to 18% of the coordinated salary depending on age, employer at least 50%), accident insurance (occupational accidents paid by the employer) and family allowances.
For sole proprietorship, the monthly payslip is only the visible part: instalments to the funds, annual settlements and certificates form the real cycle, January to January.

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 sole proprietorship, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.
Rümlang: what changes, what does not
Working with a fiduciary from Rümlang no longer depends on geography: the documents of a business in Rümlang are shared online, while the canton Zurich keeps its own deadlines for the tax return.
For a business in Rümlang, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Zurich.
Frequently asked questions
Does MyFiducia.ai work for a business based in Rümlang?
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 Rümlang manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Rümlang as everywhere in Switzerland.
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 Rümlang as anywhere.
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.
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MyFiducia.ai automates sole proprietorship for businesses in Rümlang: 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.