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Bookkeeping for architecture firms in Castel San Pietro without the stress: how it works

Bookkeeping for architecture firms in Castel San Pietro raises the same questions for most Swiss SME owners: which obligations apply, which deadlines are running, which documents to prepare. This page covers the federal rules in force — without unnecessary jargon.

The Swiss legal frame for bookkeeping

Swiss accounting law has been unified in the Code of Obligations since 2013: the same bookkeeping rules (art. 957a CO) and retention rules (art. 958f CO — 10 years for books, vouchers and reports) apply regardless of legal form. Bookkeeping sits squarely within this frame, including for companies based in Castel San Pietro.

Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For bookkeeping, 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.

Digitalising bookkeeping: 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.

The selection criterion for a tool is not the length of its feature list but the robustness of the daily flow: reliable bank imports, VAT computed correctly (8.1 / 2.6 / 3.8%), a complete audit trail from document to entry, and a clean export for the auditor or fiduciary. Everything else is secondary.

A Swiss SME's accounting calendar

Three families of deadlines shape the year: federal (VAT within 60 days, salary declaration in January), cantonal (tax return, extensions depending on the canton, including in Castel San Pietro) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.

For bookkeeping, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.

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A well-structured SME chart of accounts

Nearly all Swiss SMEs rely on the standard SME chart of accounts (Sterchi/Käfer): classes 1 (assets) to 9 (closing), with revenue in class 3 and expenses in classes 4 to 6. Using this standard structure makes conversations with your fiduciary, auditor and tax administration far easier.

Standard numbering also enables automation: stable posting rules (same supplier, same account) make data entry predictable and the audit faster. Avoid changing the chart of accounts mid-year — migrate at the closing date, with a documented mapping table.

Castel San Pietro: what changes, what does not

Castel San Pietro (postal code 6873, canton Ticino) applies the same federal rules as the rest of the country: what changes in Castel San Pietro are the cantonal counterparts — tax administration, compensation office, commercial register.

Castel San Pietro requires no special bookkeeping: the Code of Obligations applies at postal code 6873 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

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 much does bookkeeping cost in Castel San Pietro?

It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.

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.

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 Castel San Pietro too.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates bookkeeping 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.

The application is operated in French.

    Bookkeeping for architecture firms in Castel San Pietro