
Everything that matters about tax advisory benefits in Eiken
Whether you run a Sàrl, an SA or a sole proprietorship in Eiken, 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
For an owner in Eiken, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.
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.
Outsource tax advisory or keep it in-house?
Splitting roles clearly avoids duplication: the company captures documents and approves payments; the fiduciary checks postings, closes the year and defends the file before the authorities. Each side does what it does best — and nobody keys the same invoice twice.
For tax advisory, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
A Swiss SME's accounting calendar
Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.
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
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.
Eiken: what changes, what does not
Working with a fiduciary from Eiken no longer depends on geography: the documents of a business in Eiken are shared online, while the canton Aargau keeps its own deadlines for the tax return.
Eiken requires no special bookkeeping: the Code of Obligations applies at postal code 5074 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Eiken too.
What are the legal obligations for tax advisory in Switzerland?
The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Eiken: federal law applies.
Do you need a fiduciary for tax advisory, 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 Eiken.
How much does tax advisory cost in Eiken?
It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.
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MyFiducia.ai automates tax advisory for businesses in Eiken: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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