
Everything that matters about annual closing common mistakes in Porrentruy
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 Porrentruy.
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 company in Porrentruy that presents clean, punctual annual accounts gains credibility — with its bank, its suppliers and the tax administration.
A Swiss SME's accounting calendar
January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.
For annual closing, 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 annual closing or keep it in-house?
Responsibility stays with the client: the fiduciary executes with care, but the signed accounts bind the company. Understanding what you sign is not optional.
Three signals say it is time to delegate more: missed deadlines (VAT, AHV), entries running months behind, or an owner spending evenings on receipts instead of the business. Conversely, an SME equipped with modern software can safely take day-to-day entry back in-house.

The Swiss legal frame for annual closing
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. Annual closing sits squarely within this frame, including for companies based in Porrentruy.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For annual closing, 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.
Porrentruy: what changes, what does not
Porrentruy (postal code 2900, canton Jura) applies the same federal rules as the rest of the country: what changes in Porrentruy are the cantonal counterparts — tax administration, compensation office, commercial register.
For a business in Porrentruy, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Jura.
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 Porrentruy, family allowances follow the canton's rates.
Do you need a fiduciary for annual closing, 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 Porrentruy.
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 Porrentruy too.
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 Porrentruy as anywhere.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates annual closing for businesses in Porrentruy: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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