
Accounting example in Solothurn: rules, deadlines, best practice
Whether you run a Sàrl, an SA or a sole proprietorship in Solothurn, accounting 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 accounting
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Solothurn with a clean audit trail sails through these exercises.
Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.
A well-structured SME chart of accounts
The same chart serves three readings: accounting (accuracy), tax (accepted adjustments) and management (margins by activity). Modern software produces all three views without double entry.
For a business in Solothurn, comparability over time beats sophistication: a chart stable for five years beats a “perfect” one rebuilt every year. Banks and the tax administration read year-on-year movements first.
Digitalising accounting: what actually works
Digitising does not mean hoarding PDFs: without the document-entry link, a digital file is as opaque as a box of archives — true in Solothurn as everywhere.
The selection criterion for a tool is not the length of its feature list but the robustness of the daily flow: reliable bank imports, VAT computed correctly (8.1 / 2.6 / 3.8%), a complete audit trail from document to entry, and a clean export for the auditor or fiduciary. Everything else is secondary.

Outsource accounting or keep it in-house?
The Swiss fiduciary market is dense and governed by professional practice: industry standards, business secrecy, civil liability. Compare offers on three concrete criteria — exact scope (data entry? closing? payroll? VAT?), a named contact person, and the tools used. It prevents year-end misunderstandings.
A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.
Solothurn: what changes, what does not
Working with a fiduciary from Solothurn no longer depends on geography: the documents of a business in Solothurn are shared online, while the canton Solothurn keeps its own deadlines for the tax return.
Solothurn requires no special bookkeeping: the Code of Obligations applies at postal code 4500 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
Can accounting 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 accounting.
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 Solothurn too.
Do you need a fiduciary for accounting, 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 Solothurn.
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 Solothurn: the CO dictates it, not the commune.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting for businesses in Solothurn: 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.