Advisor handing a document and pen to a client

Social security contributions for law firms in Thônex: what every SME should know

Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Thônex.

The Swiss legal frame for social security contributions

A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Thônex as anywhere.

For social security contributions, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.

Digitalising social security contributions: what actually works

Artificial intelligence has changed the economics of social security contributions: automatic invoice reading reaches recognition rates that make manual entry marginal, and posting suggestions learn from corrections. The accountant does not disappear — the job shifts from data entry to control and advice.

Electronic archiving is fully recognised: Swiss bookkeeping regulation admits electronic retention of records provided integrity and readability are guaranteed for the 10 years of art. 958f CO. A paper binder is no longer an obligation — provided the archiving system is serious.

Outsource social security contributions or keep it in-house?

Outsourcing does not exempt you from understanding: an owner who can read the balance sheet and the income statement challenges the fiduciary better — and pays for advice, not re-keying.

A business in Thônex can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — social security contributions splits very well.

Team analysing financial charts around a table

A Swiss SME's accounting calendar

An accounting calendar only lives if it is shared: owner, in-house bookkeeper and fiduciary must see the same deadlines and the same status — the rule holds for every SME in Thônex.

Delays rarely come alone: neglected bookkeeping postpones the closing, hence the tax return, hence the recalculated instalments — and the business flies blind for months. Keeping the books current as you go is the only sustainable way to hold every cascading deadline.

Thônex: what changes, what does not

Sole proprietorship, Sàrl or SA in Thônex: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Geneva.

For a business in Thônex, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Geneva.

Frequently asked questions

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 Thônex can therefore archive fully digitally.

Effective VAT method or net tax rate: how to choose?

The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Thônex as anywhere.

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 Thônex: the CO dictates it, not the commune.

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 Thônex: 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.

    Social security contributions for law firms in Thônex