QR-bill invoicing for architecture firms in Lengnau (AG): rules, deadlines, best practice
Whether you run a Sàrl, an SA or a sole proprietorship in Lengnau (AG), QR-bill invoicing eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Digitalising QR-bill invoicing: what actually works
Accounting digitalisation always follows the same path: capture documents at the source (photo or PDF upload), let automatic recognition extract supplier, amount, date and VAT, approve the proposed entries, then archive each document linked to its entry. Every step removes a re-keying — and therefore an error source.
The selection criterion for a tool is not the length of its feature list but the robustness of the daily flow: reliable bank imports, VAT computed correctly (8.1 / 2.6 / 3.8%), a complete audit trail from document to entry, and a clean export for the auditor or fiduciary. Everything else is secondary.
The Swiss legal frame for QR-bill invoicing
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. QR-bill invoicing sits squarely within this frame, including for companies based in Lengnau (AG).
Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.
A well-structured SME chart of accounts
Nearly all Swiss SMEs rely on the standard SME chart of accounts (Sterchi/Käfer): classes 1 (assets) to 9 (closing), with revenue in class 3 and expenses in classes 4 to 6. Using this standard structure makes conversations with your fiduciary, auditor and tax administration far easier.
In an SME in Lengnau (AG), the chart of accounts is also a delegation tool: clear posting rules let a non-accountant prepare most entries without error.
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.
The winning trio remains: QR-bills for collections, e-banking connected to the accounts for statement imports (camt.053), and automatic matching rules. Exceptions — partial payments, duplicates, missing references — are then handled in minutes, not hours.
Lengnau (AG): what changes, what does not
Sole proprietorship, Sàrl or SA in Lengnau (AG): the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
For a business in Lengnau (AG), that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
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 Lengnau (AG) as anywhere.
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 Lengnau (AG) can therefore archive fully digitally.
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 Lengnau (AG): federal law applies.
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 Lengnau (AG): the CO dictates it, not the commune.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates QR-bill invoicing for businesses in Lengnau (AG): 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.