Everything that matters about SA incorporation for architecture firms in Untersiggenthal
Whether you run a Sàrl, an SA or a sole proprietorship in Untersiggenthal, SA incorporation eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Choosing the structure: Sàrl, SA or sole proprietorship
The choice of legal form turns on three axes: liability (limited to capital for Sàrl and SA, unlimited for the sole trader), taxation (economic double taxation of company profit and dividends versus direct income taxation) and pensions (the employee of their own Sàrl is subject to mandatory LPP; the self-employed insure voluntarily).
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.
Swiss VAT: rates, threshold and filings
Three rates coexist in Switzerland: 8.1% for most supplies, 2.6% for everyday essentials and 3.8% for accommodation. Businesses staying under CHF 100,000 a year are exempt from registration but may opt in voluntarily — useful to reclaim input VAT on investments.
Also useful for SA incorporation: some supplies are excluded from VAT (health, education, property rental) — with no corresponding input VAT right. Qualifying revenues correctly from the start avoids surprises.
Salaries and social contributions: the rates to know
Absences are managed upstream: illness, accident, military service or maternity trigger allowances (APG, insurance) that replace part of the salary. Clean absence records are the basis of correct settlements, in Untersiggenthal as elsewhere.
For SA incorporation, the monthly payslip is only the visible part: instalments to the funds, annual settlements and certificates form the real cycle, January to January.
Digitalising SA incorporation: what actually works
Artificial intelligence has changed the economics of SA incorporation: automatic invoice reading reaches recognition rates that make manual entry marginal, and posting suggestions learn from corrections. The accountant does not disappear — the job shifts from data entry to control and advice.
For SA incorporation, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.
Untersiggenthal: what changes, what does not
Working with a fiduciary from Untersiggenthal no longer depends on geography: the documents of a business in Untersiggenthal are shared online, while the canton Aargau keeps its own deadlines for the tax return.
For a business in Untersiggenthal, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
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 Untersiggenthal, family allowances follow the canton's rates.
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 Untersiggenthal.
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 Untersiggenthal 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 Untersiggenthal can therefore archive fully digitally.
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