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Sole proprietorship digitalisation in Lenzburg explained simply

Delegate, digitalise or do it all yourself? Around sole proprietorship in Lenzburg, 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.

Choosing the structure: Sàrl, SA or sole proprietorship

Articles and internal organisation are written to last: circle of shareholders, transfer of shares, signature rights. Templates do the job at first, but every missing clause gets renegotiated later from a weaker position.

Sole proprietorship starts on day one: founding capital, notary and register fees are the first entries. Opening a separate business bank account immediately — even for a sole proprietorship — saves hours of sorting private from business.

The Swiss legal frame for sole proprietorship

Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Lenzburg.

One simple principle drives sole proprietorship: 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.

Swiss VAT: rates, threshold and filings

Registration happens with the Federal Tax Administration and yields a VAT number based on the business identifier (format CHE-xxx.xxx.xxx VAT). From then on, every invoice must state that number, the rate applied and the tax amount — three details sole proprietorship should lock down from day one to avoid retroactive fixes.

Also useful for sole proprietorship: some supplies are excluded from VAT (health, education, property rental) — with no corresponding input VAT right. Qualifying revenues correctly from the start avoids surprises.

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Salaries and social contributions: the rates to know

A Swiss salary reads in three columns: gross, employee social deductions, employer contributions. Confusing them distorts cost prices — and quotes from businesses in Lenzburg.

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.

Lenzburg: what changes, what does not

Working with a fiduciary from Lenzburg no longer depends on geography: the documents of a business in Lenzburg are shared online, while the canton Aargau keeps its own deadlines for the tax return.

For a business in Lenzburg, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.

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 Lenzburg: the CO dictates it, not the commune.

Does MyFiducia.ai work for a business based in Lenzburg?

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 Lenzburg 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 Lenzburg.

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 Lenzburg: federal law applies.

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Switch to accounting that keeps itself up to date

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

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    Sole proprietorship digitalisation in Lenzburg — Swiss guide