
Limited statutory audit for engineering firms in Arbon explained simply
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on limited statutory audit in Arbon: what the law requires, what can be automated, and when to delegate.
Year-end closing: how the mechanics work
Accrual accounting is the technical heart of the closing: every income and every expense belongs to the year it economically concerns, regardless of the payment date. Rents paid in advance, insurance premiums straddling the date, supplier invoices arriving in January: all flow through accrual accounts.
The notes complete the figures: valuation principles, liabilities towards pension institutions, contingent liabilities, or the number of full-time positions. Careful notes reduce questions from the auditor and the banks.
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.
In an SME in Arbon, the chart of accounts is also a delegation tool: clear posting rules let a non-accountant prepare most entries without error.
A Swiss SME's accounting calendar
Tax instalments are steered: too low, they set up a salty final bill; too high, they tie up cash. Adjusting them on current figures is a profitable reflex, in Arbon as anywhere.
For limited statutory audit, deadline discipline is worth real money: default interest on late VAT, AHV adjustments, tax fines. A shared deadline calendar — fed by up-to-date figures — remains the simplest safeguard.

Outsource limited statutory audit or keep it in-house?
Splitting roles clearly avoids duplication: the company captures documents and approves payments; the fiduciary checks postings, closes the year and defends the file before the authorities. Each side does what it does best — and nobody keys the same invoice twice.
A business in Arbon is no longer limited to fiduciaries in its canton: with a shared online platform, collaboration works remotely, documents and entries visible to both sides in real time. The choice widens to all of Switzerland — competence becomes the criterion again, not the postcode.
Arbon: what changes, what does not
Sole proprietorship, Sàrl or SA in Arbon: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Thurgau.
For a business in Arbon, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Thurgau.
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 Arbon, family allowances follow the canton's rates.
Do you need a fiduciary for limited statutory audit, or can you do it yourself?
Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Arbon.
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 Arbon 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 Arbon too.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates limited statutory audit for businesses in Arbon: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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