
Accounting outsourcing automation in Mellingen: what every SME should know
Accounting outsourcing automation in Mellingen 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.
The Swiss legal frame for accounting outsourcing
For an owner in Mellingen, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.
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.
A Swiss SME's accounting calendar
January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.
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.
Year-end closing: how the mechanics work
Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.
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.

Digitalising accounting outsourcing: 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 accounting outsourcing: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.
Mellingen: what changes, what does not
Mellingen (postal code 5507, canton Aargau) applies the same federal rules as the rest of the country: what changes in Mellingen are the cantonal counterparts — tax administration, compensation office, commercial register.
Mellingen requires no special bookkeeping: the Code of Obligations applies at postal code 5507 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
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 Mellingen too.
Does MyFiducia.ai work for a business based in Mellingen?
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 Mellingen manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Mellingen: the CO dictates it, not the commune.
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 Mellingen, family allowances follow the canton's rates.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting outsourcing for businesses in Mellingen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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