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Sole proprietorship for fitness centres in Lenzburg: the practical guide

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.

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.

For an SME in Lenzburg, electronic filing of VAT returns has been mandatory since 1 January 2025; the tax administration's online portal is also where extensions are requested and past periods consulted. Combined with accounts that prepare the return automatically, sole proprietorship stops being a quarterly chore.

Salaries and social contributions: the rates to know

Family allowances are financed by the employer through a cantonal compensation fund — rates and amounts vary from canton to canton, including in Lenzburg. They come on top of the federal social insurances and appear on every payslip.

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.

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Digitalising sole proprietorship: what actually works

Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.

Migrate in stages: supplier invoices first (high volume, immediate gain), then receivables with the QR-bill, finally payroll and the closing. At each stage, comparing one month before/after is enough to prove the gain — no theoretical promises needed.

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.

Lenzburg requires no special bookkeeping: the Code of Obligations applies at postal code 5600 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 Lenzburg: the CO dictates it, not the commune.

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 Lenzburg can therefore archive fully digitally.

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 Lenzburg too.

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 Lenzburg, family allowances follow the canton's rates.

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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 for fitness centres in Lenzburg