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VAT return for engineering firms in Thônex explained simply

Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on VAT return in Thônex: what the law requires, what can be automated, and when to delegate.

The Swiss legal frame for VAT return

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 Thônex.

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.

Swiss VAT: rates, threshold and filings

Registration happens with the Federal Tax Administration and yields a VAT number based on the business identifier (format CHE-xxx.xxx.xxx VAT). From then on, every invoice must state that number, the rate applied and the tax amount — three details VAT return should lock down from day one to avoid retroactive fixes.

For an SME in Thônex, electronic filing of VAT returns has been mandatory since 1 January 2025; the tax administration's online portal is also where extensions are requested and past periods consulted. Combined with accounts that prepare the return automatically, VAT return stops being a quarterly chore.

Digitalising VAT return: 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 VAT return, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

Team analysing financial charts around a table

Outsource VAT return or keep it in-house?

Responsibility stays with the client: the fiduciary executes with care, but the signed accounts bind the company. Understanding what you sign is not optional.

For VAT return, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.

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.

Federal deadlines do not move in Thônex: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1226 changes nothing about those rules, only the sender's address.

Frequently asked questions

How long must records related to VAT return 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.

Do you need a fiduciary for VAT return, 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 Thônex.

Can VAT return 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 VAT return.

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 Thônex too.

Also worth reading

In neighbouring municipalities

Switch to accounting that keeps itself up to date

MyFiducia.ai automates VAT return 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.

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