
Accounting software with AI in Trey: rules, deadlines, best practice
Whether you run a Sàrl, an SA or a sole proprietorship in Trey, accounting software eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Digitalising accounting software: what actually works
Access for the fiduciary, the auditor and employees is set by roles: view, enter, approve, close. Well-set rights protect the data and speed up collaboration.
Migrate in stages: supplier invoices first (high volume, immediate gain), then receivables with the QR-bill, finally payroll and the closing. At each stage, comparing one month before/after is enough to prove the gain — no theoretical promises needed.
QR-bills and friction-free collections
Since 30 September 2022, the QR-bill has fully replaced the old Swiss payment slips. The Swiss QR Code carries the IBAN (or QR-IBAN), the amount, the debtor and a structured reference: enough to match every incoming payment to its invoice automatically.
Used properly, the QR reference removes most manual debtor ticking. For accounting software, that means reminders triggered on reliable data and continuously readable cash flow — no more waiting for month-end to know who has paid.
The Swiss legal frame for accounting software
Whether a business sits in Trey or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for accounting software. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For accounting software, 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.

Outsource accounting software 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 accounting software, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
Trey: what changes, what does not
Sole proprietorship, Sàrl or SA in Trey: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Vaud.
Federal deadlines do not move in Trey: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 1552 changes nothing about those rules, only the sender's address.
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 Trey as anywhere.
Does MyFiducia.ai work for a business based in Trey?
Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Trey manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Trey.
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 Trey as everywhere in Switzerland.
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MyFiducia.ai automates accounting software for businesses in Trey: 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.