Payment reminders in Switzerland: when to send, escalate or write off

Three terms used throughout

• Mahnung is a formal payment reminder: any unambiguous demand that the client pay a specific invoice. No form is prescribed, an oral demand counts in law, but only a dated, written one can be proved later, so that is what you send.
• Verzug is default: the legal state in which the client is late, from which point 5% default interest accrues (Art. 102 and 104 CO).
• Betreibung is the Swiss debt-enforcement procedure run by the cantonal enforcement office (Betreibungsamt): you file a request, the office serves a payment order on the debtor, and a court becomes involved only if the debtor objects.

When are you allowed to send a payment reminder in Switzerland?

From the morning after the due date. Swiss law imposes no waiting period between an invoice becoming due and your first reminder. What it does fix is the point at which the client is in default (Verzug), since interest starts there, and that point turns on one question: was the due date agreed with the client, or does it only appear on your invoice?

Payment terms in Switzerland are for you and the client to agree; no statute prescribes them. Thirty days is the convention. An invoice that is silent on payment can be demanded at once, which in practice means on receipt (Art. 75 CO).

The conclusion from the table is a two-part habit: give every invoice a calendar due date, and put the payment terms into the quote or the terms the client accepts, so that the date is agreed rather than merely printed.

Done that way, interest accrues by itself from the following day, and you remain free to remind the client on top, as a nudge and as a dated record. "Within 30 days" on the invoice alone grants the period and then waits for you to act before anything happens. Invoices created in SoloDesk, a Swiss accounting app for sole proprietors and small businesses, carry a fixed due date for precisely this reason.

How quickly should you chase?

With an agreed due date you could send the first of your payment reminders in Switzerland the next morning, or go straight to the enforcement office. Neither is usually the best opening move. In our experience with sole proprietors and small firms, the useful question is not "how many days do I wait" but "why is this particular debtor silent".

The reasons differ by type of client, and so does the step that tends to get the money moving.

Treat the table as what we see work, not as a rulebook.

The schedule below sits in the middle of that range and is our recommendation, not a legal requirement. Shorten it for new clients, lengthen it for public bodies.

Can I charge a reminder fee in Switzerland?

Only where your terms and conditions provide for it and the client accepted those terms; without such a clause the client may simply decline to pay the fee. Common practice is no fee on the first reminder and CHF 20 to 30 from the second. A fee that is in your accepted terms is added to the reminder; one that is not should be left off, because it weakens an otherwise clean demand.

The first reminder is also the stage at which many clients are not yet in default at all (see the table above), which is a second reason it usually carries no fee.

How do I calculate default interest in Switzerland?

Default interest applies by law at 5% a year from the day of default, higher only where a higher rate was agreed (Art. 104 CO), and it needs no clause in your terms. The arithmetic is:

Default interest = amount × 5% × days in default ÷ 365

For CHF 1,800 after 30 days: 1,800 × 0.05 × 30 ÷ 365 = CHF 7.40. For CHF 4,200 after 63 days: 4,200 × 0.05 × 63 ÷ 365 = CHF 36.25.

Interest keeps running until the day of payment, which is why a final notice should claim the principal "plus default interest at 5% from [date of default] until payment" rather than a frozen figure; a frozen figure invites the debtor to pay exactly that amount and leave the rest. This is also exactly how the enforcement request states a claim (principal and interest start date), so the final notice and the filing will match.

What does a Betreibung cost, and what does it actually do?

The final notice ahead of enforcement (Betreibung) should name the date after which you will file, because filing is the one step in the whole sequence that costs you money up front.

The office fee for issuing, registering and serving the payment order (Zahlungsbefehl) is graded by the amount claimed (Art. 16 para. 1 GebV SchKG). Postage for the registered delivery to the debtor and for your own copy is added, in practice around CHF 10 to 15, and each further delivery attempt costs CHF 7 (Art. 16 para. 3). You advance fee and postage; the debtor owes both on top of the claim (Art. 68 DEBA), and if the debtor pays, they come back to you with it.

Two things follow from filing: the office serves the payment order on the debtor, and the case appears in the debtor's enforcement register, visible to other creditors, landlords and banks for five years after the proceedings close (Art. 8a para. 4 DEBA). The procedure itself is set out by the Federal Office of Justice and on ch.ch; this article keeps to what your decision requires.

The payment order sets two clocks. The debtor has 20 days to pay (Art. 69 DEBA) and 10 days to object (Rechtsvorschlag) with a single sentence; no reason has to be given (Art. 74 and 75 DEBA). The ten days are the ones that decide everything. An objection halts the enforcement. To restart it you ask the court to lift the objection, and in the quick summary procedure (provisional Rechtsöffnung, Art. 82 DEBA) the court will only do so on the strength of a document the debtor signed that acknowledges the debt: a signed quote or contract together with proof that you delivered, or a signed payment plan. Your own invoice, a delivery note or an ordinary email is not a signed acknowledgment; they remain evidence, but only in an ordinary civil claim with its own costs and months.

In practice: the register entry is the real pressure. A company that would have ignored three letters often pays within days of receiving the payment order because an open enforcement entry costs it the next lease, the next supplier credit or the next bank conversation. The pressure has a limit, though. If the debtor objects, they can apply, any time from three months after service until the entry would expire anyway, to have it hidden from third parties; the office then gives you 20 days to prove you have started proceedings to lift the objection, and the entry is also hidden if those proceedings are finally rejected (Art. 8a para. 3 let. d DEBA, in force since 1 January 2026). The practical rule: file a Betreibung only if you are prepared to go on to the court step if the debtor objects.

If the debtor neither pays nor objects, the enforcement does not move by itself: you must file a continuation request (Fortsetzungsbegehren) between 20 days and one year after service of the payment order (Art. 88 DEBA). Miss the year and you start again with a new filing and a new fee.

How the enforcement continues depends on who the debtor is (Art. 39 DEBA). Against a private customer or a sole proprietor not entered in the commercial register, it continues by seizure of assets; if there is nothing to seize, you receive a certificate of shortfall (Verlustschein), enforceable for 20 years (Art. 149a DEBA). Against a GmbH, an AG or a registered sole proprietor, it continues by a bankruptcy warning (Konkursandrohung) and, if still unpaid, bankruptcy; a company will usually pay before that point, which is why the enforcement entry works so well against companies.

At what amount is a Betreibung worth it?

There is no legal threshold, and the fee table is a poor guide: the same CHF 7 applies to a CHF 50 claim and a CHF 99 claim, and the law is indifferent to whether the debtor can pay. Whether enforcement is worth it comes down to three questions, not to the amount alone.

The three-question test before Betreibung

1. Proof. Do you hold something the debtor signed that acknowledges the debt: a signed quote or contract (plus proof you delivered), or a signed payment plan? An order email or a delivery note is weaker and will not carry the summary procedure on its own.
2. Solvency. What does the debtor's enforcement-register extract (Betreibungsregisterauszug) show? It is ordered from the enforcement office for the debtor's address at a flat CHF 17 at the counter, CHF 18 by post, online or electronically, and CHF 22 by registered post (Art. 12a GebV SchKG); you must show a credible interest, which an unpaid invoice is. Existing enforcements or certificates of shortfall on the extract mean you would be queuing behind others.
3. Amount. Is the claim worth the fee, a possible court step to lift an objection, the continuation request, and the months this takes?

Three times yes: file. Any no: use another lever, or write off.

Four levers work without an enforcement office, each with its own legal footing.

• Hold back further work. Where the client still owes you payment under the same contract, you may as a rule withhold your remaining performance until the open invoice is settled (Art. 82 CO), unless the contract obliges you to perform first. A genuinely new order you can simply decline; no statute is needed for that. With an ongoing client this is the strongest lever available, and it costs nothing.
• A signed payment plan. A plan the debtor signs is an acknowledgment of the debt. It is exactly the document the court wants if an objection ever has to be lifted, and it restarts the limitation period from the date of signature (Art. 135 CO). Insist on dated instalments and one signature.
• File, then withdraw. The payment order often produces the payment on its own. The debtor owes the fee and postage as well as the claim (Art. 68 DEBA). Withdraw the enforcement only once both have been paid: a withdrawal hides the entry from third parties (Art. 8a para. 3 let. c DEBA), and with it goes your leverage for the costs.
• A collection agency. Swiss agencies work on commission, and that commission cannot be charged to the debtor as enforcement costs (Art. 27 para. 3 DEBA). On one small invoice the commission eats the claim; agencies make sense for a book of receivables, not for one CHF 380 bill.

Which invoices are actually open? Checking before you chase

In the small businesses we work with, a surprising share of what looks like an unpaid invoice in Switzerland turns out to have been paid, misdirected or disputed rather than ignored, and a reminder sent in those cases does more damage than a late one. A client who settled last week and then receives a formal reminder with interest on it will remember the reminder longer than the project.

Three situations account for nearly all of these false alarms, and each has a specific fix.

• The money arrived but was never matched to the invoice. Swiss payments match automatically only when the 27-digit QR reference travels with them. Three habits break that: the client types the amount in by hand and leaves the reference out, rounds CHF 1,798.50 up to CHF 1,800, or settles two or three invoices in one transfer under one reference. The money is on your account; the invoice still reads as open in your list.

Before you write, search the statement by payer name and by approximate amount, not by reference. If you find the payment, book it against the invoice (or, for a combined transfer, ask the client which invoices it covers before you allocate it), and send nothing.

• The invoice went to the wrong legal entity or a stale address. This is common with clients who converted a sole proprietorship into a GmbH during the year, or who moved. Legally the original client usually remains liable, and if the business was transferred to the new company, that company may be jointly liable with them (Art. 181 CO); so the invoice is not void, but it may never have landed on anyone's desk. Check the current entity name and seat in the commercial register at zefix.ch, re-address the invoice to the right entity and send it again with a short note; count the payment period from the new delivery, not from the original date, if you want the relationship to survive.
• The invoice is disputed, not forgotten. If the client has queried the amount, the scope or what was delivered, the silence is a position, not an oversight. A formal reminder here hardens it. Reply to the dispute first, in writing: if the claim stands, say why and confirm the due date; if part of it is wrong, cancel and re-issue the invoice for the correct amount, because a reminder on a figure you later reduce is a reminder you will have to withdraw. Interest keeps running on the justified part throughout; a dispute does not pause it.

If your invoices are created in SoloDesk, the first of these checks stops being a monthly chore. The invoice is created once; each month you upload the bank statement, and SoloDesk itself finds the payment in it and matches it to the invoice. Only invoices with no matching payment remain on the dashboard, so the ones you chase are the ones that are really open.

When should you write off an unpaid invoice, and what happens in your books?

Write off an unpaid invoice in Switzerland when it fails the three-question test, when enforcement ends in a certificate of shortfall, or when the debtor is bankrupt.

Writing off changes nothing in law, the claim still exists; it changes your books, which now say you no longer expect the money. To write off bad debt in Switzerland you book three things: the loss, the bad-debt provision (Delkredere) that may have preceded it, and the VAT.

• The loss. The open receivable is booked as a bad-debt loss (Debitorenverlust) and reduces your taxable profit in the year you write it off. Keep the reminders, the register extract or the certificate of shortfall in the file; the tax office may ask why the claim was hopeless.
• The provision. A bad-debt provision (Delkredere) is the value adjustment you book while the outcome is still open, so that doubtful receivables are not carried at full value. The Federal Tax Administration's practice, as published on the federal SME portal, accepts a flat rate without proof of 5% on Swiss receivables and 10% on foreign ones. Cantonal practice follows the same pattern with local variations: Bern, for example, applies 5% on Swiss receivables, 10% on foreign receivables in francs and 15% on foreign receivables in other currencies (Bern TaxInfo); Zurich publishes no official rate; the 10% and 20% often quoted there are practice values to be agreed with the tax office. Check your own canton's guidance before booking. The provision is booked at year-end as a deduction from receivables against an expense account and released when the invoice is paid or written off.
• The VAT. VAT on unpaid invoices in Switzerland (MWST / TVA) depends on how you report it. If you report on invoiced amounts (vereinbarte Entgelte, the standard method), you paid the VAT when you issued the invoice; once the receivable is lost, you deduct it as a reduction of consideration in box 235 of a later VAT return and the tax comes back (Art. 41 VAT Act). If you report on received amounts (vereinnahmte Entgelte), a payment that never arrived was never taxed and there is nothing to correct. The net tax rate method (Saldosteuersatz) does not change this logic: a net-rate business that reports on invoiced amounts also deducts the lost receivable in box 235, and gets back VAT at its net rate rather than at 8.1%. Sole proprietors on cash-basis bookkeeping, allowed below CHF 500,000 in revenue (Art. 957 para. 2 CO), have nothing to adjust for income tax, because the invoice was never booked as income; whether they have a VAT correction still depends on their VAT method, and a cash-basis bookkeeper who is VAT-registered and reports on invoiced amounts does deduct the loss in box 235.

What if the June invoice is still open at year-end?

In law, nothing: the year-end is an accounting date, not a legal deadline, and the claim stays enforceable until the limitation period runs out. In the books, a double-entry business keeps the receivable on the balance sheet and adjusts it if it is doubtful; a cash-basis business has nothing to do because nothing was booked.

The one practical step before 31 December is to make sure a dated formal reminder exists, so that the start of interest and the state of the file are documented inside the closed year.

When does an unpaid invoice become time-barred in Switzerland?

After ten years for most business claims, and after five years for the categories listed in Art. 128 CO: rent, craft work, retail sales of goods, and the professional services of doctors, lawyers and a few other named professions (Art. 127 and 128 CO). The services of a designer, consultant, developer or most other sole proprietors are not on the five-year list, so for most readers of this article the period is ten years, counted from the due date (Art. 130 CO). The clock restarts whenever the debtor acknowledges the debt, in writing or by conduct (a signed payment plan, a part payment, a payment of interest, a request for more time), and whenever you file for enforcement or sue (Art. 135 CO). A reminder on its own does not interrupt the limitation period, however many you send. Within that period there is no deadline by which you must act; the pace is yours.

Worked example

Lea is a graphic designer in Winterthur with two open invoices. Every figure below follows from the rules above.

Invoice A: CHF 1,800, a private customer, agreed date. Issued 1 June 2026, "payable by 1 July 2026", a date that was part of the quote the customer accepted. On 2 July the customer is therefore in default without any letter (Art. 102 para. 2 CO), and interest of CHF 1,800 × 5% ÷ 365 = CHF 0.25 a day starts to run. On 8 July CHF 1,800 arrives with no QR reference and is matched to the invoice by amount and payer, so the invoice drops off the overdue list and no reminder goes out. In practice: six days of interest, CHF 1.48, are not worth a letter, and Lea lets them go.

Invoice B: CHF 4,200, a GmbH, "30 days net". Issued 1 July 2026, due 1 August. The first of August passes and nothing changes in law, because no calendar date was agreed; default begins only with Lea's email of 12 August, which names the invoice and asks for payment (Art. 102 para. 1 CO), and from 13 August interest runs at CHF 4,200 × 5% ÷ 365 = CHF 0.58 a day. (Had the GmbH's signed quote contained the "30 days net" term, a court might treat that as an agreed, determinable date with default from 2 August; Lea's reminder costs her eleven days of interest and removes the argument, which is the better trade.) A formal reminder on 1 September and a final notice on 22 September, naming 10 October as the last day, bring no reply, so Lea runs the three-question test. Proof: the GmbH signed her quote and she holds the delivery confirmation, so yes. Solvency: the register extract, ordered online for CHF 18, is clean, so yes. Amount: the office fee is CHF 60 for a claim between CHF 1,000 and CHF 10,000, plus roughly CHF 12 postage, and the GmbH owes both on top of the claim (Art. 68 DEBA), so yes. In practice: on 15 October she files online, claiming CHF 4,200 plus 5% interest from 13 August, by then 63 days at CHF 0.58, about CHF 36. Rather than carry a register entry, the GmbH pays within days of receiving the payment order: CHF 4,200, about CHF 36 of interest and the CHF 72 of fee and postage, which the enforcement office had added to the claim. Only then does Lea withdraw the enforcement.

The contrast: CHF 380, a private customer, two existing enforcements. Proof is thin (an email order), the register extract shows two open enforcements, and the office fee would be CHF 20 plus postage for a CHF 380 claim. The test fails on solvency and on amount. In practice: Lea writes the invoice off as a bad-debt loss, keeps the extract in the file, and, because she reports VAT on invoiced amounts, deducts the CHF 380 (which included 8.1% VAT) in box 235 of her next return to recover the CHF 28.47 of VAT it contained.

How SoloDesk handles payment reminders

SoloDesk is a Swiss accounting app for sole proprietors and small businesses. Among the things it handles in your bookkeeping are invoices, over their whole life cycle: from creation to payment matching and reminders.

• Invoices are created in the app with a Swiss QR-bill and a fixed calendar due date; the app itself runs in German, French, Italian and English.
• Each month you upload your bank statement; SoloDesk finds the incoming payments in it and matches them to the open invoices automatically, so a settled invoice never shows as overdue.
• Invoices still unmatched after their due date appear as overdue on the dashboard when you log in.
• For each overdue invoice, a first, second and final reminder are prepared from the invoice itself, with the days overdue and the 5% default interest already calculated. You only decide when to send; the reminder is logged against the invoice.
• Open receivables and your current VAT position are shown on the dashboard.

Here is how the same work looks with a template and a bank export, and how it looks in SoloDesk.