
Tax advisory alternatives in Aarau: the practical guide
Whether you run a Sàrl, an SA or a sole proprietorship in Aarau, tax advisory 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 tax advisory
Three documents summarise the health of a Swiss business: the balance sheet (what it owns), the income statement (what it earns) and the notes (what else you should know). All the work of tax advisory converges on those three pages, in Aarau too.
The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.
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 tax advisory, a closing checklist reused every year transforms the exercise: same steps, same checks, same documents — only the year changes.
Outsource tax advisory 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.

A Swiss SME's accounting calendar
An accounting calendar only lives if it is shared: owner, in-house bookkeeper and fiduciary must see the same deadlines and the same status — the rule holds for every SME in Aarau.
An SME in Aarau that holds its calendar twelve months straight changes its position: fewer official reminders, easier extensions — and tax advisory stops being a source of worry.
Aarau: what changes, what does not
Aarau (postal code 5000, canton Aargau) applies the same federal rules as the rest of the country: what changes in Aarau are the cantonal counterparts — tax administration, compensation office, commercial register.
Federal deadlines do not move in Aarau: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5000 changes nothing about those rules, only the sender's address.
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.
What is the difference between a limited and an ordinary audit?
The ordinary audit applies to companies exceeding, for two consecutive years, two of three thresholds: CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions. Others fall under the limited audit, and those with no more than ten full-time positions on annual average can opt out with all shareholders' consent. These federal thresholds do not depend on the registered seat — in Aarau as anywhere.
Does MyFiducia.ai work for a business based in Aarau?
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 Aarau manages its documents, VAT and exports exactly as anywhere in Switzerland.
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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MyFiducia.ai automates tax advisory for businesses in Aarau: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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