
Fiduciary services for IT companies in Erlen: rules, deadlines, best practice
Fiduciary services for IT companies in Erlen 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 fiduciary services
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. Fiduciary services sits squarely within this frame, including for companies based in Erlen.
The good news: the Swiss frame is stable and predictable. Structure fiduciary services once — chart of accounts, document flow, calendar — and the same organisation pays off for years.
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 Erlen that presents clean, punctual annual accounts gains credibility — with its bank, its suppliers and the tax administration.
Digitalising fiduciary services: what actually works
Automation is judged on the exceptions: what happens when the document is unreadable, the supplier unknown, the amount divergent? A good tool isolates those cases and lets a human decide fast — precious for teams in Erlen.
The winning pair for fiduciary services: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.

Outsource fiduciary services 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.
For fiduciary services, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
Erlen: what changes, what does not
Sole proprietorship, Sàrl or SA in Erlen: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Thurgau.
For a business in Erlen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Thurgau.
Frequently asked questions
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 Erlen 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 Erlen as anywhere.
What is simplified bookkeeping and who can use it?
Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Erlen.
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 Erlen: the CO dictates it, not the commune.
Also worth reading
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates fiduciary services for businesses in Erlen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
The application is operated in French.