
Accounting outsourcing for e-commerce in Onex: rules, deadlines, best practice
Accounting outsourcing for e-commerce in Onex raises the same questions for most Swiss SME owners: which obligations apply, which deadlines are running, which documents to prepare. This page covers the federal rules in force — without unnecessary jargon.
The Swiss legal frame for accounting outsourcing
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.
One simple principle drives accounting outsourcing: 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.
A Swiss SME's accounting calendar
The typical annual cycle: monthly or quarterly AHV instalments, VAT returns (quarterly under the effective method, semi-annual under the net tax rate), the final salary declaration in January, closing in the first half-year, then the tax return and the annual VAT reconciliation. Each link depends on the quality of the previous one.
For accounting outsourcing, 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.
Outsource accounting outsourcing 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.
Three signals say it is time to delegate more: missed deadlines (VAT, AHV), entries running months behind, or an owner spending evenings on receipts instead of the business. Conversely, an SME equipped with modern software can safely take day-to-day entry back in-house.

Year-end closing: how the mechanics work
The income statement reads as a cascade: gross margin, operating result, financial result, extraordinary result. Each level answers a different question — mixing levels blurs the steering.
For accounting outsourcing, the golden rule is to discover nothing in January: every uncertainty (doubtful receivable, dispute, unsellable stock) must be identified before the closing date, not after.
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.
Federal deadlines do not move in Onex: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1213 changes nothing about those rules, only the sender's address.
Frequently asked questions
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.
Which social contributions does a Swiss employer pay?
AHV/IV/APG: 5.3% employer share (the same is withheld from the employee); unemployment insurance: 1.1% each up to CHF 148,200 a year; occupational pension (LPP) by age and plan (employer at least 50%); occupational accident insurance paid by the employer; family allowances by canton. For an employer in Onex, family allowances follow the canton's rates.
What are the legal obligations for accounting outsourcing 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 Onex: 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 Onex: the CO dictates it, not the commune.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting outsourcing for businesses in Onex: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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