Pro Forma Invoices in Switzerland: What They Are and When to Use Them

A pro forma invoice is a preliminary document — a quotation in invoice form. It is used for customs declarations, prepayments, or when a client needs a formal price confirmation before committing.

Pro forma vs. real invoice

A pro forma invoice must be clearly labelled as such and should not carry your normal invoice number. It is a draft or an offer, not a demand for payment.

A pro forma invoice does not trigger VAT or a bookkeeping entry. Nothing is posted until the real invoice is issued and the transaction actually happens.

The real invoice is what creates the obligation and the tax consequence. The pro forma merely communicates the terms in a familiar invoice-like format.

Because the two look alike, the label is everything. A pro forma that is not marked as pro forma can be mistaken for a real invoice and paid, or booked, by accident.

• Always label it “Pro forma” clearly.
• Do not reuse your invoice number sequence.
• Issue a real invoice once the deal is confirmed.

Common uses

Customs authorities often ask for a pro forma invoice for international shipments. It lets them value the goods and calculate duties before the actual commercial invoice is issued.

Clients ask for a pro forma when they need internal approval before raising a purchase order. It gives their procurement team a formal document to sign off on.

A pro forma is also used to request a prepayment. The client can pay against the pro forma, but you still issue the real invoice when the deal is confirmed and the money is due.

For quotations that need to look official — tenders, grants, or partner submissions — a pro forma provides the invoice format without the legal weight of a real invoice.

Keeping them apart

Use a distinct numbering range for pro forma documents, such as PF-001, so they can never collide with your real invoice sequence. This alone prevents most mix-ups.

Do not include payment details that imply a demand. A pro forma may show a price, but it should not read like an invoice that is immediately due.

If you use the same template for pro forma and real invoices, add a visible watermark or banner such as “Pro forma — not a demand for payment” so the two are instantly distinguishable.

Train anyone who handles your documents to check the label. The most common mistake is a pro forma being sent to bookkeeping and posted as if it were a real invoice.

Converting to a real invoice

When the client confirms, issue a real invoice with a proper number from your main sequence. The pro forma is then retired and the real document takes over the bookkeeping.

The real invoice should carry its own invoice date and, if applicable, the service date or period. These may differ from the pro forma, especially if the deal was confirmed weeks later.

If the client already prepaid against the pro forma, the real invoice should show the prepayment as a deduction, leaving only the remaining balance due.

Reference the pro forma number on the real invoice so the two documents are linked. A short note such as "per pro forma PF-014" keeps the paper trail complete.

• Use a separate PF- numbering range.
• Add a clear “Pro forma” watermark or banner.
• Issue the real invoice with a normal number on confirmation.
• Offset any prepayment on the real invoice.