
Everything that matters about VAT return for law firms in Onex
Whether you run a Sàrl, an SA or a sole proprietorship in Onex, VAT return 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 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 Onex.
One simple principle drives VAT return: every franc in or out must be explainable by a document, an entry and an account. All of Swiss accounting law fits inside that traceability requirement.
Digitalising VAT return: what actually works
Access for the fiduciary, the auditor and employees is set by roles: view, enter, approve, close. Well-set rights protect the data and speed up collaboration.
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 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, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.

Swiss VAT: rates, threshold and filings
Since 1 January 2024, Swiss VAT rates are 8.1% (standard), 2.6% (reduced — food, books, medicines) and 3.8% (accommodation). Registration becomes mandatory from CHF 100,000 of worldwide annual turnover. For VAT return, step one is therefore checking the threshold and choosing the right reporting method.
Returns are filed quarterly (effective method) or twice a year (net tax rate method). Either way the rule is identical: file and pay within 60 days after the end of the period. An annual reconciliation with the accounts is required — this is where sloppy data entry gets expensive.
Onex: what changes, what does not
Sole proprietorship, Sàrl or SA in Onex: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Geneva.
For a business in Onex, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Geneva.
Frequently asked questions
What is simplified bookkeeping and who can use it?
Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Onex.
Does MyFiducia.ai work for a business based in Onex?
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 Onex manages its documents, VAT and exports exactly as anywhere in Switzerland.
How much does VAT return cost in Onex?
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.
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 Onex can therefore archive fully digitally.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates VAT return for businesses in Onex: 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.