
Everything that matters about SA incorporation for construction companies in Castel San Pietro
Delegate, digitalise or do it all yourself? Around SA incorporation in Castel San Pietro, 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
A Sàrl requires CHF 20,000 of fully paid-in capital; an SA CHF 100,000 of which at least CHF 50,000 paid in. Both require a notarised deed and entry in the commercial register. A sole proprietorship arises from mere activity — registration only becomes mandatory from CHF 100,000 of annual revenue.
Incorporating in Castel San Pietro opens the same toolbox: banks, funds, fiduciaries and online tools work everywhere — the choice of seat is strategic, not technical, for SA incorporation.
Digitalising SA incorporation: what actually works
Digitising does not mean hoarding PDFs: without the document-entry link, a digital file is as opaque as a box of archives — true in Castel San Pietro as everywhere.
The winning pair for SA incorporation: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.
The Swiss legal frame for SA incorporation
A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Castel San Pietro as anywhere.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For SA incorporation, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.

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 Castel San Pietro.
A thirteenth salary, where agreed, is accrued month by month — forget it and December reveals a charge of one-twelfth of the payroll, in Castel San Pietro as everywhere.
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.
For a business in Castel San Pietro, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Ticino.
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 Castel San Pietro: the CO dictates it, not the commune.
What is the difference between a limited and an ordinary audit?
The ordinary audit applies to companies exceeding, for two consecutive years, two of three thresholds: CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions. Others fall under the limited audit, and those with no more than ten full-time positions on annual average can opt out with all shareholders' consent. These federal thresholds do not depend on the registered seat — in Castel San Pietro as anywhere.
Effective VAT method or net tax rate: how to choose?
The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Castel San Pietro as anywhere.
How long must records related to SA incorporation 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.
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