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Accounting outsourcing for construction companies in Würenlos: the practical guide

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 Würenlos.

The Swiss legal frame for accounting outsourcing

A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Würenlos as anywhere.

Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For accounting outsourcing, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.

A Swiss SME's accounting calendar

An accounting calendar only lives if it is shared: owner, in-house bookkeeper and fiduciary must see the same deadlines and the same status — the rule holds for every SME in Würenlos.

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.

Outsource accounting outsourcing or keep it in-house?

A good test before choosing: ask the fiduciary HOW it wants to receive the documents. A precise answer (formats, frequency, platform) says more than any brochure — including in Würenlos.

A business in Würenlos can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — accounting outsourcing splits very well.

Collaborative desk with laptops and documents, top view

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.

For accounting outsourcing, a closing checklist reused every year transforms the exercise: same steps, same checks, same documents — only the year changes.

Würenlos: what changes, what does not

Working with a fiduciary from Würenlos no longer depends on geography: the documents of a business in Würenlos are shared online, while the canton Aargau keeps its own deadlines for the tax return.

Federal deadlines do not move in Würenlos: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5436 changes nothing about those rules, only the sender's address.

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 Würenlos, family allowances follow the canton's rates.

What are the current Swiss VAT rates?

Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Würenlos.

Which documents should be prepared for the year-end closing?

Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in Würenlos: the CO dictates it, not the commune.

What are the legal obligations for accounting outsourcing 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 Würenlos: federal law applies.

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Switch to accounting that keeps itself up to date

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

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