
Sàrl incorporation deadlines in Spreitenbach without the stress: how it works
Whether you run a Sàrl, an SA or a sole proprietorship in Spreitenbach, Sàrl incorporation eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
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.
On the Sàrl incorporation side, the first financial year may be longer or shorter than a calendar year: choosing the first closing date wisely avoids a pointless mini-closing.
The Swiss legal frame for Sàrl incorporation
Three documents summarise the health of a Swiss business: the balance sheet (what it owns), the income statement (what it earns) and the notes (what else you should know). All the work of Sàrl incorporation converges on those three pages, in Spreitenbach too.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For Sàrl incorporation, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.
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.
An employer in Spreitenbach does well to fix payday on a set day of the month: funds, employees and cash flow organise around it, and Sàrl incorporation becomes routine instead of a sprint.

Digitalising Sàrl incorporation: what actually works
A serious accounting document archive links every record to its entry, timestamps versions and logs access — exactly what Swiss bookkeeping regulation expects from probative electronic retention. Chronological filing by financial year becomes an automatic by-product.
The winning pair for Sàrl incorporation: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.
Spreitenbach: what changes, what does not
Working with a fiduciary from Spreitenbach no longer depends on geography: the documents of a business in Spreitenbach are shared online, while the canton Aargau keeps its own deadlines for the tax return.
For a business in Spreitenbach, 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 Spreitenbach too.
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 Spreitenbach.
Does MyFiducia.ai work for a business based in Spreitenbach?
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 Spreitenbach manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Spreitenbach: the CO dictates it, not the commune.
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MyFiducia.ai automates Sàrl incorporation for businesses in Spreitenbach: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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