
E-invoicing for law firms in Onex: the practical guide
E-invoicing for law firms in Onex rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.
Digitalising e-invoicing: 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.
The winning pair for e-invoicing: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.
Outsource e-invoicing 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.
Changing fiduciary is not a drama: the accounting data belongs to the company, and a clean export (entries, chart of accounts, linked documents) allows a transition at year-end. A provider who locks in a client's data says a lot about how it works.
QR-bills and friction-free collections
Clear payment terms, a visible due date, exact details: half of late payments come from ambiguous invoices, not bad payers — the finding holds in Onex too.
For the debtors of a business in Onex, nothing changes on the payer's side: scan the code, confirm, pay. On the e-invoicing side, everything changes: the collection entry proposes itself, the receivables ledger updates continuously and reminders go out on exact balances.

The Swiss legal frame for e-invoicing
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Onex with a clean audit trail sails through these exercises.
For e-invoicing, 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.
Onex: what changes, what does not
Onex (postal code 1213, canton Geneva) applies the same federal rules as the rest of the country: what changes in Onex are the cantonal counterparts — tax administration, compensation office, commercial register.
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
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 Onex as everywhere in Switzerland.
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 Onex too.
How long must records related to e-invoicing 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.
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.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing 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.