
SME tax return in Switzerland in Eiken: rules, deadlines, best practice
Delegate, digitalise or do it all yourself? Around SME tax return in Eiken, every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.
The Swiss legal frame for SME tax return
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Eiken with a clean audit trail sails through these exercises.
One simple principle drives SME tax return: 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
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.
The useful reflex: date every obligation the moment it arises. An employee hired means AHV/LPP deadlines created; VAT registration means a filing cycle set; a closing date fixed means backward planning of the close. Well organised, the SME tax return calendar fills itself.
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.
Also useful for SME tax return: some supplies are excluded from VAT (health, education, property rental) — with no corresponding input VAT right. Qualifying revenues correctly from the start avoids surprises.

Year-end closing: how the mechanics work
Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.
For SME tax return, a closing checklist reused every year transforms the exercise: same steps, same checks, same documents — only the year changes.
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
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 Eiken: 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 Eiken too.
How long must records related to SME tax return 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 Eiken can therefore archive fully digitally.
Which social contributions does a Swiss employer pay?
AHV/IV/APG: 5.3% employer share (the same is withheld from the employee); unemployment insurance: 1.1% each up to CHF 148,200 a year; occupational pension (LPP) by age and plan (employer at least 50%); occupational accident insurance paid by the employer; family allowances by canton. For an employer in Eiken, family allowances follow the canton's rates.
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