
QR-bill invoicing for agencies in Trey: rules, deadlines, best practice
QR-bill invoicing for agencies in Trey rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.
Digitalising QR-bill invoicing: 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 Trey as everywhere.
For QR-bill invoicing, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.
A well-structured SME chart of accounts
The test of a good chart of accounts is a single question: can the owner find the margins in three clicks? If not, the chart serves the tax office but not the business — even in Trey.
The chart of accounts is also the hinge to VAT: every revenue account carries its rate (8.1%, 2.6%, 3.8% or exempt), every expense account its input-tax right. Set those attributes once in the tool and every subsequent return becomes reliable.
Outsource QR-bill invoicing or keep it in-house?
Splitting roles clearly avoids duplication: the company captures documents and approves payments; the fiduciary checks postings, closes the year and defends the file before the authorities. Each side does what it does best — and nobody keys the same invoice twice.
For QR-bill invoicing, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.

The Swiss legal frame for QR-bill invoicing
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Trey with a clean audit trail sails through these exercises.
One simple principle drives QR-bill invoicing: 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.
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.
Trey requires no special bookkeeping: the Code of Obligations applies at postal code 1552 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
What are the legal obligations for QR-bill invoicing 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 Trey: federal law applies.
How long must records related to QR-bill invoicing be kept?
Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders. A business in Trey can therefore archive fully digitally.
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.
Can QR-bill invoicing be automated with AI?
Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches QR-bill invoicing.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates QR-bill invoicing 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.