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Social security contributions for physiotherapy practices in Sisseln without the stress: how it works

Whether you run a Sàrl, an SA or a sole proprietorship in Sisseln, 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 Sisseln.

Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For social security contributions, 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.

A Swiss SME's accounting calendar

January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.

For social security contributions, deadline discipline is worth real money: default interest on late VAT, AHV adjustments, tax fines. A shared deadline calendar — fed by up-to-date figures — remains the simplest safeguard.

Digitalising social security contributions: 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.

For social security contributions, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

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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.

For social security contributions, the gap between agreed gross and paid net surprises every new employer: simulate it BEFORE hiring to avoid misunderstandings with the future employee.

Sisseln: what changes, what does not

Sisseln (postal code 4334, canton Aargau) applies the same federal rules as the rest of the country: what changes in Sisseln are the cantonal counterparts — tax administration, compensation office, commercial register.

Sisseln requires no special bookkeeping: the Code of Obligations applies at postal code 4334 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

Do you need a fiduciary for social security contributions, or can you do it yourself?

Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Sisseln.

What are the legal obligations for social security contributions in Switzerland?

The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Sisseln: federal law applies.

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 Sisseln: the CO dictates it, not the commune.

Does MyFiducia.ai work for a business based in Sisseln?

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 Sisseln manages its documents, VAT and exports exactly as anywhere in Switzerland.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates social security contributions for businesses in Sisseln: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

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    Social security contributions in Sisseln