Booking supplier invoices automatically: the checks that make it safe

The short answer

Yes, for routine bills. A recurring invoice from a known supplier, in Swiss francs, with a clean QR-bill and one VAT rate can be booked without a click. The condition is that the software proves each reading before it books, and hands everything else to a person together with the reason: not “error”, but “the VAT rows do not add up to the total”.

What does not work is trusting a model because it sounds sure: it reads a blurred total as confidently as a sharp one. Safety comes from checks that run after the reading.

What “automatic” should mean

“Automatic” covers three steps, and it helps to keep them apart when you compare software:

• Reading the bill. Supplier, invoice number, date, amounts, VAT and payment details are taken from the PDF or the scan.
• Proposing the booking. The software suggests the expense account and the VAT code, usually based on earlier bills from the same supplier.
• Booking without a click. The entry is posted with no approval, and only when every check passes. If one fails, the bill waits for a person.

Many products do the first two and call it automatic, while someone still approves each entry. The third step is only as safe as the checks behind it.

The checks that matter

Each check answers one question: could this reading be wrong without anyone noticing? Good software runs all of them on every bill.

• Two independent readings. The bill is read once from the page image and once from the text in the file. If the two disagree on amount, date or invoice number, nothing is booked.
• Arithmetic. Net amounts plus VAT must give the total, row by row. A bill that does not add up was misread or is wrong.
• The QR-bill. The amount and currency in the Swiss QR code must match the printed total. A total in euros above a payment part in francs needs a person.
• The recipient. The bill must be addressed to your company, not to a sister company or a private person.
• Duplicates. The same invoice number, supplier and amount, or the same file arriving by email and again as a scan, is booked once.
• Document type. Reminders, credit notes, delivery notes and account statements look like invoices. A reminder booked as a new bill doubles the expense.
• VAT. The rate must be one that was valid for the date on the bill: Swiss rates changed on 1 January 2024, so a bill for work done in 2023 still carries the old one. Reverse charge on services from abroad and import VAT are read from the documents, not guessed, and a company on the net tax rate method (Saldosteuersatz) books no input tax at all.
• The date. A bill dated in a locked period, or in the future, is held rather than booked into the wrong month.
• The exchange rate. A bill in euros or dollars is booked only when a rate for that day is available. Without one, it waits.

What should never be automatic

Some steps should wait for a person, whatever the software could do:

• the year-end closing;
• releasing payroll;
• locking a period.

Corrections follow the same logic. A wrong entry is corrected with a reversal entry (Storno), never by deleting it, and a log shows who booked what and when: a person, a rule or the AI. Your accountant can then follow every figure back to its document.

The controls an owner needs

Even with every check in place, you decide how much the software does alone. Any product you consider should offer four controls:

• An autonomy level you choose. From “every change needs a click” to “everyday bookings are automatic”, with steps in between.
• A pause switch. One click stops all automatic booking, for example during the audit.
• A monthly cost cap. AI is paid by usage. A cap you set keeps a busy month from turning into an unexpected bill.
• A “please check” list. Every point the software was unsure about, in one place, with the document and the reason.

Honest limits

A model can read a field and still be unsure about it: a handwritten amount, a stamp over the date, two totals on one page. Good software then books the bill and marks the point for review, or holds the bill.

Choosing the right expense account is the hard part. Whether a bill is office supplies or equipment to capitalise depends on your company, not on the document. That deserves an accountant’s spot checks, especially in the first months.

Be careful with accuracy figures. A number measured on someone else’s bills says little about yours. Measure on your own bills before you trust any figure.

How to start

Do not begin with full automation. Begin where a mistake costs nothing:

1. Set the software to read-only or approval mode, so it proposes bookings but posts nothing.
2. Run one month of real supplier bills through it.
3. Compare its proposals, entry by entry, with what your accountant or fiduciary actually booked.
4. Look at the differences: wrong readings, wrong accounts, and bills it was right to hold.
5. Widen step by step: first recurring bills from known suppliers, later the rest.

If the comparison is not good enough, stay in approval mode. Approving a prepared booking is still less work than typing it.

At MomentumQ

We automated our own accounting with software we built, and we build custom solutions for Swiss companies whose bookkeeping needs a workflow of its own.