
Social security contributions for IT companies in Oensingen: the practical guide
Whether you run a Sàrl, an SA or a sole proprietorship in Oensingen, social security contributions 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 social security contributions
Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Oensingen.
The good news: the Swiss frame is stable and predictable. Structure social security contributions once — chart of accounts, document flow, calendar — and the same organisation pays off for years.
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 Oensingen does well to fix payday on a set day of the month: funds, employees and cash flow organise around it, and social security contributions becomes routine instead of a sprint.
A Swiss SME's accounting calendar
Three families of deadlines shape the year: federal (VAT within 60 days, salary declaration in January), cantonal (tax return, extensions depending on the canton, including in Oensingen) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.
For social security contributions, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.

Outsource social security contributions or keep it in-house?
A good test before choosing: ask the fiduciary HOW it wants to receive the documents. A precise answer (formats, frequency, platform) says more than any brochure — including in Oensingen.
A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.
Oensingen: what changes, what does not
Working with a fiduciary from Oensingen no longer depends on geography: the documents of a business in Oensingen are shared online, while the canton Solothurn keeps its own deadlines for the tax return.
For a business in Oensingen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Solothurn.
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 Oensingen as everywhere in Switzerland.
Does MyFiducia.ai work for a business based in Oensingen?
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 Oensingen manages its documents, VAT and exports exactly as anywhere in Switzerland.
How long must records related to social security contributions 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 Oensingen can therefore archive fully digitally.
Can social security contributions 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 social security contributions.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates social security contributions for businesses in Oensingen: 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.