
Sole proprietorship required documents in Castel San Pietro: what every SME should know
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on sole proprietorship in Castel San Pietro: what the law requires, what can be automated, and when to delegate.
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 Castel San Pietro as elsewhere.
A Sàrl and an SA must also appoint an auditor, unless they opt out (no more than ten full-time positions on annual average and unanimous shareholder consent). Many young companies start without one, then appoint an auditor when growth or investors demand it.
Digitalising sole proprietorship: what actually works
Access for the fiduciary, the auditor and employees is set by roles: view, enter, approve, close. Well-set rights protect the data and speed up collaboration.
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.
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 Castel San Pietro too.
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.

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 Castel San Pietro. They come on top of the federal social insurances and appear on every payslip.
For sole proprietorship, the monthly payslip is only the visible part: instalments to the funds, annual settlements and certificates form the real cycle, January to January.
Castel San Pietro: what changes, what does not
Sole proprietorship, Sàrl or SA in Castel San Pietro: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Ticino.
Federal deadlines do not move in Castel San Pietro: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 6873 changes nothing about those rules, only the sender's address.
Frequently asked questions
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 Castel San Pietro, family allowances follow the canton's rates.
Does MyFiducia.ai work for a business based in Castel San Pietro?
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 Castel San Pietro manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Castel San Pietro can therefore archive fully digitally.
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 Castel San Pietro.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in Castel San Pietro: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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