Sole proprietorship required documents in Aarau: what every SME should know
Whether you run a Sàrl, an SA or a sole proprietorship in Aarau, sole proprietorship eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
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 Aarau as elsewhere.
Settling in Aarau 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
Three documents summarise the health of a Swiss business: the balance sheet (what it owns), the income statement (what it earns) and the notes (what else you should know). All the work of sole proprietorship converges on those three pages, in Aarau too.
The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.
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.
Salaries and social contributions: the rates to know
The salary certificate is an official tax document: it feeds the employee's tax return and serves as the reference in AHV and tax audits. Issued once a year, it must match payroll accounting and the declaration to the compensation office to the centime.
Withholding tax applies to foreign employees without a C permit: the employer deducts tax at the cantonal rate and remits it. The annual salary certificate remains mandatory for all staff — it is the linchpin connecting payroll accounting, tax returns and AHV audits.
Aarau: what changes, what does not
Aarau (postal code 5000, canton Aargau) applies the same federal rules as the rest of the country: what changes in Aarau are the cantonal counterparts — tax administration, compensation office, commercial register.
Federal deadlines do not move in Aarau: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5000 changes nothing about those rules, only the sender's address.
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 Aarau can therefore archive fully digitally.
Does MyFiducia.ai work for a business based in Aarau?
Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Aarau manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Aarau.
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 Aarau too.
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