
SME tax return for startups in Kaiseraugst explained simply
SME tax return for startups in Kaiseraugst rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.
The Swiss legal frame for SME tax return
In Switzerland, the duty to keep accounts stems from art. 957 ff. of the Code of Obligations. Legal entities (Sàrl, SA) and sole proprietorships with at least CHF 500,000 in revenue keep full accounts: balance sheet, income statement and notes. Below that threshold, a simplified record of income, expenses and assets is sufficient.
Also worth knowing: accounts may be drawn up in the currency most relevant to the business; if that is not the franc, values must additionally be stated in CHF (art. 958d para. 3 CO). Internationally active companies gain books that match their economic reality.
Year-end closing: how the mechanics work
Accrual accounting is the technical heart of the closing: every income and every expense belongs to the year it economically concerns, regardless of the payment date. Rents paid in advance, insurance premiums straddling the date, supplier invoices arriving in January: all flow through accrual accounts.
For an SME in Kaiseraugst, the closing is also decision time: distributions, provisions, investments to anticipate. A file ready in February leaves time to decide; one ready in June just endures.
Outsource SME tax return or keep it in-house?
A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of SME tax return lowers fees more surely than any negotiation.
In Kaiseraugst, as everywhere, the right collaboration rhythm follows the activity: monthly for payroll and data entry, quarterly for VAT, yearly for the closing and tax advice.

A Swiss SME's accounting calendar
Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.
For SME tax return, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.
Kaiseraugst: what changes, what does not
Working with a fiduciary from Kaiseraugst no longer depends on geography: the documents of a business in Kaiseraugst are shared online, while the canton Aargau keeps its own deadlines for the tax return.
For a business in Kaiseraugst, 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 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 Kaiseraugst.
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 Kaiseraugst as anywhere.
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 Kaiseraugst as everywhere in Switzerland.
Which social contributions does a Swiss employer pay?
AHV/IV/APG: 5.3% employer share (the same is withheld from the employee); unemployment insurance: 1.1% each up to CHF 148,200 a year; occupational pension (LPP) by age and plan (employer at least 50%); occupational accident insurance paid by the employer; family allowances by canton. For an employer in Kaiseraugst, family allowances follow the canton's rates.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates SME tax return for businesses in Kaiseraugst: 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.