Everything that matters about sole proprietorship for architecture firms in Lumino
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Lumino.
Choosing the structure: Sàrl, SA or sole proprietorship
Settling in Lumino does not change federal law, but the canton shapes what follows: profit and capital tax rates, family allowances, possible start-up support. Comparing seriously before fixing the seat can pay off — moving a company later costs more.
On the sole proprietorship side, the first financial year may be longer or shorter than a calendar year: choosing the first closing date wisely avoids a pointless mini-closing.
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.
For an SME in Lumino, 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
The salary certificate is an official tax document: it feeds the employee's tax return and serves as the reference in AHV and tax audits. Issued once a year, it must match payroll accounting and the declaration to the compensation office to the centime.
For sole proprietorship, the winning mechanics are simple: one single payroll database (salaries, rates, allowances), monthly slips generated from it, and an annual declaration that is little more than a sum. Painful catch-up invoices almost always stem from scattered data.
The Swiss legal frame for sole proprietorship
Whether a business sits in Lumino or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for sole proprietorship. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
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.
Lumino: what changes, what does not
Sole proprietorship, Sàrl or SA in Lumino: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Ticino.
For a business in Lumino, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Ticino.
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 Lumino as anywhere.
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 Lumino: federal law applies.
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 Lumino.
Does MyFiducia.ai work for a business based in Lumino?
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 Lumino manages its documents, VAT and exports exactly as anywhere in Switzerland.
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