Invoicing Software for Fiduciaries (Rechnungssoftware Treuhänder): Managing Many Clients

A Treuhandbüro rarely invoices for itself alone. The core of the business is the mandate: you send the invoices of dozens of client companies, in their name and under their UID. Software built for one company hits its limits fast.

What makes fiduciary invoicing different

Start with the name on the document. Under a mandate the client bills and your office operates: each invoice carries the client's branding, address and UID, and the money lands on the client's account. The tool must separate issuer from operator.

Then comes variety. A portfolio spans sole proprietorships, GmbHs and associations, each with its own numbering circle, payment terms and invoice language. One legal entity per login is the assumption that breaks.

VAT is the sharpest edge. One client stays exempt below the CHF 100,000 turnover threshold.[1] The next charges the 8.1% standard rate and the 2.6% reduced rate.[2] A third uses the flat-rate Saldosteuersatz. The scheme belongs to the client, not your login.

Every invoice ends with a QR-bill, which has been in circulation since June 2020 and definitively replaced the old payment slips on 1 October 2022. Its Swiss QR code carries all the information necessary for the payment.[3] The tool must build it on each client's QR-IBAN, never on yours.

The multi-client features that matter

Templates come first: one master layout with each client's logo, wording and footer as overrides. Draft once, render in the client's identity — the difference between a billing system and a mail merge.

Numbering needs an independent circle per client that continues what you inherit. Take over a mandate at invoice 2417 and the next document is 2418: no gaps, no restarts, no explanations when the auditor samples the sequence.

Recurring billing is where hours come back: retainers, rents and subscriptions run monthly across the portfolio in one batch, each in the right currency, language and VAT scheme, each with a correct QR-bill.

Dunning must also work in the client's name. Reminders escalate from friendly to firm in the tone each client chooses, open items stay tracked per mandate, and a Mahnung reaching a client's customer never mentions your office.

Compliance that travels with the mandate

Retention is the heavyweight: books, records and vouchers are kept for ten years under Art. 958f of the Code of Obligations, with the GeBüV governing electronic storage.[4] Each client's documents must remain separately retrievable, outliving any software relationship.

Your office is also a financial intermediary: under the Anti-Money-Laundering Act it must join a FINMA-recognised self-regulatory organisation (SRO),[5] and the client-identification records behind that duty belong in the same system as the invoices.

An audit trail earns its keep once several staff share mandates: who created, changed, sent or voided which document, and when. When the ESTV audits a client, that trail is what the auditor wants to see.

Data protection rounds it off. The revised FADP has been in force since 1 September 2023,[6] and a fiduciary's database holds the financial life of entire companies. Role-based access and clean access logs are professional standard, not extras.

Choosing and rolling out the software

Shortlist against the portfolio, not the demo: per-client VAT schemes, QR-bill output, numbering circles, roles, retention and accounting exports decide the result. Then test the finalist on two real mandates: one exempt small business, one with mixed rates.

Pricing deserves a spreadsheet. Vendors charge per user, per mandate or per entity, and a tool that is cheap at five clients can outgrow its welcome at fifty. Model the portfolio's growth before committing.

Migrate in the quiet season: import client masters and open items first, continue each numbering sequence where the previous bookkeeper left it, then parallel-run one month. Clients should notice nothing except that the QR-bill scans.

facturio was built for Swiss freelancers, SMEs and fiduciaries: every invoice generates a SIX-compliant QR-bill, contacts and products are managed in one place, and payment reminders run automatically — the baseline a Treuhandbüro needs before it scales. Sources: [1] ESTV, VAT tax liability; [2] ESTV, Swiss VAT rates; [3] SIX, QR-bill standard; [4] KMU Portal, electronic bookkeeping; [5] FINMA, SROs; [6] FDPIC, the new Data Protection Act.