Cancelling an Invoice in Czechia 2026: Void It or Issue a Credit Note?

You just issued an invoice with the wrong amount, sent it to the wrong client, or the job it covered fell through — and now you need to know what to do about it. Before you delete or rewrite anything, you need the answer to three questions: has the invoice already reached the client, does the correction change the tax base, and are you a VAT payer or not. The answer decides whether a simple void is enough, or whether you need to issue a formal corrective tax document (opravný daňový doklad) and reflect it in your VAT control statement (kontrolní hlášení, a monthly or, for some sole traders, quarterly VAT transaction report every Czech VAT payer must file).

Getting this wrong costs more here than in most countries. Deleting an invoice that has already been sent leaves a gap in your invoice numbering sequence, rewriting an amount without a corrective document means the tax office is missing a figure in the VAT control statement, and forgetting to void a cancelled order distorts your recorded income. This article walks through the decision process for both VAT payers and non-payers, plus a sample cancellation note you can adapt.

Step 1: Has the invoice reached the client, or is it still a draft?

If you have only just created the invoice and haven't sent or handed it to the client yet, there's no problem at all. Fix it or delete it — it never entered anyone else's records or any tax filing. For an unpaid advance invoice (a "proforma" — see our guide to proforma invoices in Czechia) that has no other document linked to it yet, Taxorio lets you delete it directly.

Once an invoice has gone out — by email, through a public invoice link, or in person — stop treating it as a draft. Even a flawed invoice that has already been sent is a valid document until you formally cancel or correct it.

Step 2: Is it just a typo, or does the tax base actually change?

Not every mistake calls for a cancellation. If you swapped a letter in the client's company name or entered the wrong order number, but the amount, the VAT rate, and the description of the supply are all correct, you usually just need to agree the correction with the client and note it against the invoice. You don't need a new document or a corrective tax document, because neither the tax base nor the tax amount is affected.

But as soon as the amount changes, the supply is cancelled, or the client returns goods, you're dealing with a substantive correction that affects tax. That's when you choose between a void and a corrective tax document.

A typical borderline case is a price with one digit wrong — say 15,000 CZK instead of 1,500 CZK. Here the tax base changes, so it isn't "just" a typo, even though it's technically only one extra zero.

The five most common reasons for cancelling an invoice

In practice, cancellations come down to five recurring situations: a wrong amount (a misplaced zero or a miscalculated line item), a wrong client (the invoice went to the wrong company), a duplicate invoice (you accidentally issued two invoices for the same supply), a cancelled order (the client cancelled before you started work), and an incorrect VAT status on the document (you added VAT while you were still a non-payer, or the other way round).

Each of these follows the same underlying logic described above; they differ only in what you note as the reason on the document. For a duplicate invoice, it's worth also noting the number of the invoice that remains valid, so nobody has to guess during a later check.

Non-VAT payers: a simple void is enough — never delete a sent invoice

If you are not a VAT payer, you're only dealing with your income records, not a VAT control statement or a VAT return. For a sent invoice that falls through or contains a serious error, void it. The document keeps its status as "Cancelled", keeps its number, and stays in your numbering sequence and history, but it no longer counts towards your income. Never delete an invoice just because it's inconvenient — you'd tear a gap in a sequence that has to stay continuous, and you'd need to justify that gap if the tax office ever asks.

If a client accidentally paid an invoice that you now need to cancel, that isn't a void — it's a refund, which calls for reversing the payment or, in some cases, a credit note. If you're dealing with an overpaid deposit specifically, rather than a plain refund, see how that correction works in our guide to issuing a final invoice after an advance payment.

VAT payers: it depends on whether the document ever reached the customer

For a VAT payer, two things decide the outcome: whether the supply actually took place, and whether the customer received the document. If the invoice was created by mistake — the supply never happened, it's a duplicate, or it went to the wrong customer — and it never reached the customer, a simple void is enough: no taxable supply took place, so it has no place in your VAT return or control statement. Watch out for the opposite case: if the supply did take place and the invoice merely got lost along the way, don't void it. The obligation to declare VAT arose on the date of supply regardless, so you need to send the customer the document again.

Once the document has reached the customer and the correction changes the tax base or cancels the supply, you must issue a corrective tax document under Section 42 of the Czech VAT Act (Section 45 sets out its required content) — referencing the original invoice number, stating the reason for the correction, and showing a new, usually negative, tax base and VAT amount. A plain void without a corrective document isn't enough here, because the tax authority already has the original supply on record.

A decrease in VAT is reported in the return and the VAT control statement for the period in which the corrective document was delivered to the customer, not the period in which you issued it. An increase in VAT — for example when a price is raised after the fact — belongs to the period in which the event triggering the correction occurred.

What if you've already filed the VAT control statement

If you've already filed the VAT return and VAT control statement for the period the original invoice belongs to, the correction doesn't undo that filing by itself. Instead:

1. issue a corrective tax document referencing the original invoice,
2. work out which period the correction belongs to, based on the delivery date to the customer,
3. if that period has already been filed, submit a supplementary VAT control statement (následné kontrolní hlášení) for that period,
4. if it changes your last known tax liability, file a matching additional VAT return (dodatečné přiznání),
5. keep proof of when the corrective document was delivered to the customer, since that date determines the correction period.

Only a VAT payer files a VAT control statement — a sole trader (an individual, as opposed to a limited company) who is a quarterly payer files it quarterly; everyone else files it monthly.

Overview: situation, correct step and VAT impact

Sample cancellation note

A simple void should reference the original number, the date, and a short reason. It might read like this:

Cancellation of invoice no. 20260042 dated 3 September 2026
Reason: Invoice issued in error; the ordered supply did not take place.
This cancellation is not included in the income tax return or the VAT return.

For a corrective tax document, also state the original tax base, the corrected base, the original and corrected VAT amounts, and the section of the VAT Act under which you're making the correction.

How to avoid needing a cancellation in the first place

The cheapest cancellation is the one you never have to deal with. Before sending an invoice, check three things: the customer's Company ID (IČO) and name against the ARES public business register, the line items and VAT rate if you're a VAT payer, and the date of taxable supply (DUZP) — see our article on when a Czech sole trader taxes an invoice — which should match the actual state of the job. For new clients, it's also worth getting the scope and price confirmed in writing before you start work, ideally by email, so you can point to what was agreed if there's ever a dispute.

If you invoice the same client regularly, it's worth keeping a saved price list with the correct prices and VAT rates so you don't have to retype them by hand each time. Fewer mistakes mean fewer cancellations and less admin around corrections.

How Taxorio handles this

Taxorio separates four distinct actions so situations don't get mixed up. Delete only works on an unpaid advance invoice that has no other document linked to it — a regular issued invoice can never be deleted. Void is for a sent, unpaid invoice that you're cancelling without refunding anyone — the document gets the status "Cancelled", stays in your history and numbering sequence, doesn't count towards VAT or income, and is never automatically sent to the client.

Cancel payment is for when a payment never arrived or was recorded by mistake — for an advance invoice, this also cancels the linked tax document for the received payment. If the money genuinely arrived and you're refunding it, or the price is being reduced, that's a Credit note — a corrective tax document under Section 42 of the VAT Act. A paid invoice can no longer be edited or voided; reversing the payment or issuing a credit note is the only way forward. The history of every void and correction stays attached to the original invoice, so if the tax office ever asks, you can show exactly why and when the document changed. You can try this for free at app.taxorio.cz/register, no card required.

Official sources

• Czech VAT Act (No. 235/2004 Coll.) (in Czech)
• Czech Financial Administration: methodology for completing the VAT control statement (in Czech)