
Fiduciary services with AI in Aarau: what every SME should know
Fiduciary services with AI in Aarau 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 fiduciary services
In Switzerland, the duty to keep accounts stems from art. 957 ff. of the Code of Obligations. Legal entities (Sàrl, SA) and sole proprietorships with at least CHF 500,000 in revenue keep full accounts: balance sheet, income statement and notes. Below that threshold, a simplified record of income, expenses and assets is sufficient.
The law also settles the form: accounts may be kept in a national language or in English, on paper or electronically (art. 957a para. 5 CO). That pragmatism lets fiduciary services run entirely on digital tools — no paper binder is required.
Outsource fiduciary services or keep it in-house?
Outsourcing does not exempt you from understanding: an owner who can read the balance sheet and the income statement challenges the fiduciary better — and pays for advice, not re-keying.
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.
Year-end closing: how the mechanics work
The closing turns day-to-day bookkeeping into annual accounts: balance sheet, income statement and notes (art. 958 CO). Mandatory stops: accruals and deferrals, depreciation, commercially justified provisions, inventory of stock and work in progress, then VAT and AHV reconciliations.
For an SME in Aarau, the closing is also decision time: distributions, provisions, investments to anticipate. A file ready in February leaves time to decide; one ready in June just endures.

A Swiss SME's accounting calendar
The professionals' trick: handle every deadline at D-30, not D-1. A VAT return prepared a month early leaves time to chase a missing document without penalty.
For fiduciary services, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.
Aarau: what changes, what does not
Working with a fiduciary from Aarau no longer depends on geography: the documents of a business in Aarau are shared online, while the canton Aargau keeps its own deadlines for the tax return.
For a business in Aarau, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
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 Aarau as everywhere in Switzerland.
Effective VAT method or net tax rate: how to choose?
The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Aarau as anywhere.
Do you need a fiduciary for fiduciary services, 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 Aarau.
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 Aarau.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates fiduciary services for businesses in Aarau: 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.