
E-invoicing for law firms in Mendrisio: rules, deadlines, best practice
E-invoicing for law firms in Mendrisio 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 e-invoicing: what actually works
A serious accounting document archive links every record to its entry, timestamps versions and logs access — exactly what Swiss bookkeeping regulation expects from probative electronic retention. Chronological filing by financial year becomes an automatic by-product.
Electronic archiving is fully recognised: Swiss bookkeeping regulation admits electronic retention of records provided integrity and readability are guaranteed for the 10 years of art. 958f CO. A paper binder is no longer an obligation — provided the archiving system is serious.
A well-structured SME chart of accounts
The same chart serves three readings: accounting (accuracy), tax (accepted adjustments) and management (margins by activity). Modern software produces all three views without double entry.
For e-invoicing, a few well-chosen analytical accounts (by activity, by site) beat a forest of sub-accounts nobody ever reads.
Outsource e-invoicing or keep it in-house?
A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of e-invoicing lowers fees more surely than any negotiation.
For e-invoicing, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.

QR-bills and friction-free collections
Instalments and partial payments are handled cleanly with distinct references per tranche: each collection finds its share, and the remaining balance stays correct at all times.
For an SME in Mendrisio, receivables are an asset to manage: a weekly ageing balance, graduated reminders and a provision for doubtful cases — e-invoicing provides the numbers, discipline does the rest.
Mendrisio: what changes, what does not
Sole proprietorship, Sàrl or SA in Mendrisio: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Ticino.
Federal deadlines do not move in Mendrisio: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 6825 changes nothing about those rules, only the sender's address.
Frequently asked questions
How long must records related to e-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 Mendrisio can therefore archive fully digitally.
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 Mendrisio too.
Does MyFiducia.ai work for a business based in Mendrisio?
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 Mendrisio manages its documents, VAT and exports exactly as anywhere in Switzerland.
Can e-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 e-invoicing.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing for businesses in Mendrisio: 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.