
Tax advisory for carpenters in Aarau: rules, deadlines, best practice
Tax advisory for carpenters 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 tax advisory
Swiss accounting law has been unified in the Code of Obligations since 2013: the same bookkeeping rules (art. 957a CO) and retention rules (art. 958f CO — 10 years for books, vouchers and reports) apply regardless of legal form. Tax advisory sits squarely within this frame, including for companies based in Aarau.
One simple principle drives tax advisory: 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
Every deadline has an owner: an obligation “of everyone” is kept by no one. Naming one person per deadline family (VAT, payroll, taxes) closes the gaps.
For tax advisory, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.
Swiss VAT: rates, threshold and filings
Exports, services abroad, acquisition tax: as soon as anything international enters the picture, VAT gets demanding (place of supply, acquisition tax on services). Better to set the rules once with a professional than to correct three financial years.
For businesses in Aarau, VAT is in practice the most audited tax: punctual returns consistent with the books markedly reduce the odds of a deep audit of tax advisory.

Year-end closing: how the mechanics work
Depreciation follows rates accepted by tax practice (property, machinery, IT): staying within those ranges avoids reassessments. Exceeding them is justified — and documented, in Aarau as anywhere.
For tax advisory, a closing checklist reused every year transforms the exercise: same steps, same checks, same documents — only the year changes.
Aarau: what changes, what does not
Sole proprietorship, Sàrl or SA in Aarau: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
Aarau requires no special bookkeeping: the Code of Obligations applies at postal code 5000 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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.
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 Aarau: the CO dictates it, not the commune.
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 Aarau too.
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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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