Unpaid invoice in Switzerland: what the law says, and what to do in which order

Under Swiss law, an unpaid invoice is not enough on its own: what matters legally is the moment the customer is “in default”. That switch is what gives you rights. First, default interest of 5% a year (Art. 104 CO). Second, if the damage caused to you by the delay exceeds that interest, the part that exceeds it, unless the customer proves they were not at fault (Art. 106 CO): the interest counts towards that damage, it is not added on top. In a bilateral contract, you can also set the customer an appropriate time limit and, if they still do not perform, forgo the late performance and claim damages for non-performance, or withdraw from the contract (Art. 107 to 109 CO).

Article 102 of the Code of Obligations describes two ways to get there. Paragraph 1: “Where an obligation is due, the obligor is in default as soon as he receives a formal reminder from the obligee.” In other words, you ask for payment, and the customer is in default. Paragraph 2: “Where a deadline for performance of the obligation has been set by agreement […], the obligor is automatically in default on expiry of the deadline.” In that case the date is enough, without sending anything. These quotes come from the English translation published by Fedlex, which states that English is not an official language of the Swiss Confederation and that the translation has no legal force; the legally binding text is linked in the Sources section.

Watch out for the detail many pages leave out: paragraph 2 speaks of a deadline set BY AGREEMENT. A due date that you print on your invoice on your own, without the customer having accepted it somewhere, does not necessarily meet that condition. If your payment terms were accepted (in a signed quote, a contract, general terms and conditions), you are covered. Otherwise, a simple reminder settles the question: it counts as a formal reminder and puts the customer in default.

In practice: always put a due date on your invoices, and have your payment terms accepted at the quote or contract stage (what a Swiss quote commits you to, with a free template: quote template for Switzerland). They apply to that contract: the agreed due date puts the customer in default without a reminder (Art. 102 para. 2 CO). For later orders, repeat them in each quote or order confirmation, or have general terms and conditions accepted once that cover all your orders. If in doubt, a reminder puts the customer in default (Art. 102 para. 1 CO). The other details a Swiss invoice should carry are listed in how to invoice as a freelancer in Switzerland.

This is the least known point, and the most useful. Article 104 paragraph 1 reads: “A debtor in default on payment of a pecuniary debt must pay default interest of 5% per annum even where a lower rate of interest was stipulated by contract.” (Fedlex English translation, no legal force.)

You have nothing to agree, nothing to write into general terms and conditions, nothing to mention on the invoice. As soon as the customer is in default, the 5% runs. It is the law that grants it.

Two nuances. If your contract provides for a rate higher than 5%, that higher rate applies (Art. 104 para. 2). And in business dealings, if the bank discount rate at the place of payment is higher than 5%, the interest may be calculated at that rate (Art. 104 para. 3).

To be honest about the order of magnitude: on an invoice of CHF 1,200 paid 40 days late, default interest comes to about CHF 6.60. It is not income, it is an argument. Its real use is that it exists: mentioning it in a reminder often changes behaviour far more than the amount itself.

The Code of Obligations does not provide for reminder fees. For late payment, it provides for default interest (Art. 104). It only has damage caused by the delay made good if that damage, once proven, exceeds the interest, and only for the excess (Art. 106, which applies the principle of Art. 103 to money debts). Flat fees of CHF 20 or CHF 30 per reminder fall under neither.

You may charge them, but only if they were agreed, in a contract or in general terms and conditions accepted by the customer. Even when agreed, excessive fees can be reduced by a court: legal doctrine, probably the prevailing view according to the Federal Council, applies Art. 163 para. 3 CO by analogy for this. Without an agreement, you can only claim actual, proven damage exceeding the default interest (Art. 106 CO), for example the postage for reminders sent once the customer is in default. According to the prevailing doctrine, however, the cost of the reminder that puts the customer in default is never part of it. A flat “reminder fee” line added to a reminder when nothing had been agreed therefore has no legal basis and will rightly be disputed.

If you want to be able to charge them, the approach is simple: write a reasonable amount into your payment terms, and have those terms accepted at the quote or contract stage. Not afterwards.

Here is the usual sequence. The legal references are in the right-hand column. The law sets no time limit between reminders and requires no reminder before debt enforcement: you choose the pace.

Do not let it drag on: a tradesperson's invoice is in principle time-barred after 5 years, and a reminder does not stop that period. How it is calculated and what interrupts it is explained on our page on the limitation period of an invoice.

Fele-facture keeps the list of your paid and unpaid invoices: you mark an invoice as paid yourself. When you open the app, at most once a day, it shows you the unpaid invoices whose due date has been reached or passed (30 days after the invoice date). Nothing is sent to your customer automatically. In My documents, “🔔 Send reminder” prepares the reminder in one tap, a ready message with the invoice as a PDF, without having to look up which invoice is still open. On the Free plan, you send it with your phone or your own email app. From the Independent plan (and during the 14-day trial), Fele-facture emails it to your customer, with the invoice attached and a copy for you, when you tap “✉️ Send the reminder”. Also from the Independent plan, “🏦 Payments received” reads the camt.053/054 or CSV statement from your e-banking on your device and suggests the invoices that have been paid, which you confirm; it is not a connection to the bank.

Prices: the Free plan creates 5 invoices or quotes a month without the QR payment part; the QR-bill is included from the Independent plan (CHF 15/month); Unlimited costs CHF 29/month. The full 14-day trial needs no card.

On the other hand, we do not handle debt enforcement or debt collection, we do not calculate default interest automatically, and we do not draft legal formal notices. For debt enforcement, the office to contact is the debt enforcement office at the debtor's domicile (Art. 46 para. 1 DEBA). If your customer is a legal entity or a company registered in the commercial register (GmbH/Sàrl, AG/SA, general partnership…), it is the office at its registered office (Art. 46 para. 2 DEBA). For a disputed case, contact a lawyer or a legal protection insurer.

And to be clear about what this page is worth: we make invoicing software, we are not a law firm. The rules of law cited here refer to the text of the law (Code of Obligations, DEBA), linked at the bottom of the page: read it, it is short and free. What comes from legal doctrine or custom, rather than from the law, is marked as such.

If you are still looking for a tool, our comparison of Swiss invoicing software shows which ones include the QR-bill, which have a free plan, and at what price; the selection criteria are detailed in our guide to Swiss invoicing software (in French).