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Sole proprietorship common mistakes in Kölliken: the practical guide

Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Kölliken.

Choosing the structure: Sàrl, SA or sole proprietorship

The choice of legal form turns on three axes: liability (limited to capital for Sàrl and SA, unlimited for the sole trader), taxation (economic double taxation of company profit and dividends versus direct income taxation) and pensions (the employee of their own Sàrl is subject to mandatory LPP; the self-employed insure voluntarily).

On the sole proprietorship side, the first financial year may be longer or shorter than a calendar year: choosing the first closing date wisely avoids a pointless mini-closing.

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.

Returns are filed quarterly (effective method) or twice a year (net tax rate method). Either way the rule is identical: file and pay within 60 days after the end of the period. An annual reconciliation with the accounts is required — this is where sloppy data entry gets expensive.

Salaries and social contributions: the rates to know

Absences are managed upstream: illness, accident, military service or maternity trigger allowances (APG, insurance) that replace part of the salary. Clean absence records are the basis of correct settlements, in Kölliken as elsewhere.

A thirteenth salary, where agreed, is accrued month by month — forget it and December reveals a charge of one-twelfth of the payroll, in Kölliken as everywhere.

Advisor handing a document and pen to a client

The Swiss legal frame for sole proprietorship

A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Kölliken as anywhere.

Also worth knowing: accounts may be drawn up in the currency most relevant to the business; if that is not the franc, values must additionally be stated in CHF (art. 958d para. 3 CO). Internationally active companies gain books that match their economic reality.

Kölliken: what changes, what does not

Kölliken (postal code 5742, canton Aargau) applies the same federal rules as the rest of the country: what changes in Kölliken are the cantonal counterparts — tax administration, compensation office, commercial register.

Kölliken requires no special bookkeeping: the Code of Obligations applies at postal code 5742 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

What are the legal obligations for sole proprietorship 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 Kölliken: federal law applies.

Do you need a fiduciary for sole proprietorship, 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 Kölliken.

Can sole proprietorship 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 sole proprietorship.

How much does sole proprietorship cost in Kölliken?

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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Switch to accounting that keeps itself up to date

MyFiducia.ai automates sole proprietorship for businesses in Kölliken: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

The application is operated in French.

    Sole proprietorship common mistakes in Kölliken