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Sole proprietorship for the self-employed in Killwangen without the stress: how it works

Sole proprietorship for the self-employed in Killwangen 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.

Choosing the structure: Sàrl, SA or sole proprietorship

Check the company name before any enthusiasm: availability in the commercial register, internet domain, possible trademark. Renaming later costs time and trust, in Killwangen as elsewhere.

Settling in Killwangen also means thinking about insurance from incorporation: professional liability, property, business interruption — the accounts keep track of them and the closing allocates them correctly.

The Swiss legal frame for sole proprietorship

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. Sole proprietorship sits squarely within this frame, including for companies based in Killwangen.

For sole proprietorship, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.

Swiss VAT: rates, threshold and filings

The most frequent VAT mistakes are well known: the wrong rate among 8.1%, 2.6% and 3.8%, forgotten self-supplies, and a rushed annual reconciliation. Corrections are due at the latest in the return for the period containing the 180th day after the year-end — the earlier you correct, the less default interest runs.

The net tax rate method simplifies life for small structures: one flat industry rate applied to turnover, with semi-annual filing. In exchange, input VAT is not deducted separately. The effective-versus-flat-rate choice should be reviewed periodically against the cost structure.

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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 Killwangen 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 Killwangen as everywhere.

Killwangen: what changes, what does not

Killwangen (postal code 8956, canton Aargau) applies the same federal rules as the rest of the country: what changes in Killwangen are the cantonal counterparts — tax administration, compensation office, commercial register.

Killwangen requires no special bookkeeping: the Code of Obligations applies at postal code 8956 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

How long must records related to sole proprietorship 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 Killwangen can therefore archive fully digitally.

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 Killwangen: the CO dictates it, not the commune.

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.

What is simplified bookkeeping and who can use it?

Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Killwangen.

Also worth reading

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates sole proprietorship for businesses in Killwangen: 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 for the self-employed in Killwangen