
Tax advisory for engineering firms in Aarburg without the stress: how it works
Whether you run a Sàrl, an SA or a sole proprietorship in Aarburg, 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
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 Aarburg.
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.
Year-end closing: how the mechanics work
The order of operations matters: reconciliations first (bank, cash, receivables, payables), then the closing entries, finally the VAT and AHV consistency checks. Reversing the order means starting over.
A clean closing pays beyond the legal duty: it conditions the tax return, bank discussions and the company's value in a succession. Hidden reserves (accelerated depreciation, provisions) remain admissible within cantonal tax limits — document them systematically.
Outsource tax advisory or keep it in-house?
Outsourcing tax advisory to a fiduciary frees up time and secures compliance; keeping it in-house preserves a continuous view and costs less in fees. The best answer is often hybrid: the company captures and digitises as it goes, the fiduciary supervises, closes the books and represents the company before the authorities.
For tax advisory, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.

Swiss VAT: rates, threshold and filings
Taxable consideration is not limited to the invoiced price: barter, set-offs and benefits in kind count too. The safe reflex: every economic advantage received is documented and qualified.
Also useful for tax advisory: some supplies are excluded from VAT (health, education, property rental) — with no corresponding input VAT right. Qualifying revenues correctly from the start avoids surprises.
Aarburg: what changes, what does not
Sole proprietorship, Sàrl or SA in Aarburg: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
For a business in Aarburg, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
Frequently asked questions
How long must records related to tax advisory be kept?
Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders. A business in Aarburg can therefore archive fully digitally.
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 Aarburg too.
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 Aarburg as anywhere.
Can tax advisory 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 tax advisory.
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MyFiducia.ai automates tax advisory for businesses in Aarburg: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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