
Everything that matters about accounting for engineering firms in Mies
Accounting for engineering firms in Mies 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 accounting
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. Accounting sits squarely within this frame, including for companies based in Mies.
One simple principle drives accounting: 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.
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.
Suspense accounts (to clarify) are useful provided they are emptied monthly: a swelling “miscellaneous” account is the classic symptom of a chart that no longer fits the activity.
Digitalising accounting: what actually works
Digitising does not mean hoarding PDFs: without the document-entry link, a digital file is as opaque as a box of archives — true in Mies as everywhere.
For accounting, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

Outsource accounting or keep it in-house?
The scope goes down in writing: who enters data, who approves payments, who answers the tax office, who keeps the originals. Every “we'll see” at the start becomes a December misunderstanding — in Mies as elsewhere.
For accounting, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
Mies: what changes, what does not
Working with a fiduciary from Mies no longer depends on geography: the documents of a business in Mies are shared online, while the canton Vaud keeps its own deadlines for the tax return.
Mies requires no special bookkeeping: the Code of Obligations applies at postal code 1295 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Mies as everywhere in Switzerland.
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 Mies too.
Do you need a fiduciary for accounting, 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 Mies.
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 Mies, family allowances follow the canton's rates.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting for businesses in Mies: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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