
Everything that matters about accounting outsourcing for Sàrl companies in Seon
Whether you run a Sàrl, an SA or a sole proprietorship in Seon, accounting outsourcing eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
The Swiss legal frame for accounting outsourcing
Whether a business sits in Seon or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for accounting outsourcing. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.
Year-end closing: how the mechanics work
The CO's accounting principles frame the closing: regularity, prudence and consistency of presentation (art. 958c CO), on the going-concern assumption (art. 958a CO). In practice, that means valuation methods kept constant from one year to the next — and documented whenever they change.
For an SME in Seon, 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.
Digitalising accounting outsourcing: what actually works
Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.
For accounting outsourcing, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

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 accounting outsourcing, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.
Seon: what changes, what does not
Working with a fiduciary from Seon no longer depends on geography: the documents of a business in Seon are shared online, while the canton Aargau keeps its own deadlines for the tax return.
For a business in Seon, 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 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 Seon as anywhere.
How much does accounting outsourcing cost in Seon?
It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.
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 Seon too.
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 Seon, family allowances follow the canton's rates.
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