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Tax advisory for engineering firms in Thürnen without the stress: how it works

Tax advisory for engineering firms in Thürnen rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.

The Swiss legal frame for tax advisory

For an owner in Thürnen, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.

The law also settles the form: accounts may be kept in a national language or in English, on paper or electronically (art. 957a para. 5 CO). That pragmatism lets tax advisory run entirely on digital tools — no paper binder is required.

Year-end closing: how the mechanics work

Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.

A well-ordered closing file speeds everything up: bank statements at the closing date, a signed inventory, final AHV/LPP/accident settlements, new or amended contracts, and support for the accruals. Tax advisory in Thürnen then finishes in days, not weeks.

A Swiss SME's accounting calendar

Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.

Handing deadline monitoring to a tool is no luxury: automatic reminders, a status per obligation, and an “all green” view that clears the mind. What matters is not who ticks the box — but that the box exists and everyone can see it.

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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.

For an SME in Thürnen, 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, tax advisory stops being a quarterly chore.

Thürnen: what changes, what does not

Sole proprietorship, Sàrl or SA in Thürnen: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Basel-Country.

For a business in Thürnen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Basel-Country.

Frequently asked questions

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 Thürnen as anywhere.

What are the legal obligations for tax advisory 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 Thürnen: federal law applies.

Do you need a fiduciary for tax advisory, 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 Thürnen.

When must a business register for VAT?

As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Thürnen as everywhere in Switzerland.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates tax advisory for businesses in Thürnen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

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