Invoicing Under the Czech Flat Tax (Paušální Daň) 2026: Records You Still Must Keep

The Czech flat tax (paušální daň) is sold on one promise: a single monthly payment instead of a tax return, annual statements for social and health insurance, and full tax records. Plenty of self-employed people (OSVČ) take that to mean they don't have to write anything down or keep any paperwork at all. That's not quite true. The Income Tax Act still requires anyone on the flat tax to keep records of income from self-employment — otherwise there'd be no way to prove you actually meet the conditions of your chosen band and the overall 2,000,000 CZK limit. It's worth tracking your outstanding receivables too: without them you don't know who still owes you money, and you'll need the figure if you ever leave the flat-tax regime.

You still have to invoice exactly like any other non-VAT payer — an unbroken numbering sequence, the correct requirements, and no VAT stated anywhere. What changes is what happens to those invoices afterwards, and how long and in what form you need to hold onto them.

What the flat tax changes — and what it doesn't

The flat tax replaces income tax and both social and health insurance contributions with one monthly payment and removes the obligation to file a return or annual statements. It changes nothing about the fact that you're still running a business: you issue invoices, receive payments, and should know who still owes you money. Section 7a of the Income Tax Act therefore still requires a flat-tax payer to keep simple records that let both you and the tax office verify at any time that you meet the conditions of your chosen band.

What records you must keep

• A list of issued invoices with their payment date. For flat-tax purposes, income counts on the day you're paid, not the day you issue the invoice.
• An overview of receivables as of 31 December. You should be able to state the value of unpaid invoices at year-end — if you ever leave the flat-tax regime, they become taxable income.
• A breakdown of income by type of activity, if your income falls under different flat-rate expense percentages (60% or 80%) — this determines which band you fall into.

These records don't need a prescribed form. A simple table or an income ledger showing the amount, issue date, and payment date for each invoice is enough.

What you don't have to keep — but should hang onto anyway

You don't need expense receipts for tax purposes under the flat tax, since you don't claim any expenses. It's still worth keeping the more important ones — receipts for pricier equipment, contracts, or invoices for services you re-billed to a client. They come in handy for a warranty claim, a dispute with a supplier, or if you ever leave the flat-tax regime and need to retroactively document costs on unfinished work.

2026 flat tax bands and income thresholds

Which band you're in depends on the size and mix of your self-employment income over the full year. For 2026, the following monthly amounts and thresholds apply:

From January to June 2026, Band 1 paid 9,984 CZK a month; the resulting 4,932 CZK overpayment is credited against later payments. Example: Anna Example works as a graphic designer (60% flat-rate expense category) and occasionally teaches courses (80% category). Over 2026 she invoices 950,000 CZK in total — 700,000 CZK for design work and 250,000 CZK for courses. Because more than 75% of her income falls under the 60% or 80% category, she can stay in Band 1 even with income above 1,000,000 CZK, as long as she doesn't cross 1.5 million CZK. You'll find the exact conditions for each band in our article Czech Flat Tax for Foreigners: 2026 Bands, or check them with the flat tax calculator.

Second example: a freelance programmer using the 60% flat-rate expense category who invoices 1,900,000 CZK over 2026 needs to watch the overall 2,000,000 CZK limit far more closely than Anna in the first example — even one small extra job could push him past the flat-tax regime entirely, not just into a higher band. It's exactly this kind of income, close to the limit, where ongoing record-keeping pays off the most.

A simple recording routine

1. Issue the invoice as soon as the work is done. Write down the number, issue date, and description right away instead of reconstructing it later.
2. Note the payment date. As soon as a client pays, record the exact date — it determines which month and year the income belongs to.
3. Check unpaid invoices once a month. Chase receivables that have gone past their usual due date with a reminder before they pile up.
4. Keep a running total of income against your band threshold. Compare invoiced amounts to the 1, 1.5, or 2 million CZK limit that applies to your mix of activities.
5. Close out your receivables record at year-end. By 31 December you need an accurate list of what clients still owe you.

This routine takes roughly a quarter of an hour a week and saves you an unpleasant surprise at year-end, when you'd otherwise have to reconstruct your income from bank statements and old email threads.

It's worth keeping up the same routine even if you only invoice occasionally. Fewer invoices doesn't mean less risk of a mistake — if anything, it's the opposite, because with irregular invoicing it's easier to lose track of which invoice a client has already paid. A short, regular note is always more reliable than trying to reconstruct an entire year at once in December.

What a flat-tax payer's invoice looks like

For invoicing purposes, a flat-tax payer looks exactly like any other non-VAT payer: no VAT rate or amount appears on the document, and no VAT identification number is stated. If you're unsure about the requirements, see our detailed guide Invoice for a Non-VAT Payer in Czech Republic.

A flat-tax payer can also be an "identified person" at the same time — typically if you receive advertising or consulting services from a foreign VAT payer, or supply such services abroad yourself. The flat tax itself doesn't disappear; you simply gain an extra VAT reporting duty on top of it. More in Identified Person VAT in Czech Republic.

Advance payments: how much, and when

The flat-tax advance is due by the 20th day of the calendar month it covers — in advance, not in arrears. A late payment creates an underpayment with all the usual consequences of a late tax payment. Track the deadline with the tax deadlines tool.

What happens if you cross the 2,000,000 CZK limit

If your self-employment income for the year exceeds 2,000,000 CZK, you must notify the tax office within 15 days. You then fall out of the flat-tax regime for the entire year and return to standard taxation — with full tax records, a tax return, and annual statements for the Czech Social Security Administration and your health insurance company. This is exactly why ongoing income tracking pays off even for a flat-tax payer: it warns you well ahead of the limit instead of catching you off guard in late December.

When the flat tax stops making sense

The flat tax isn't automatically the best choice for everyone. Consider switching to flat-rate or actual expenses if you have high real costs, claim a child tax credit or other deductions that are lost under the flat tax, or need to show a higher tax base for a mortgage application. You'll find a comparison in our article Flat-Rate vs Real Expenses in Czech Republic.

How Taxorio handles this

Taxorio's flat-tax settings track the limit of your chosen band as well as the overall 2,000,000 CZK annual limit, and warn you as you approach it. You issue invoices without VAT just like any other non-VAT payer, the calendar reminds you of the advance payment deadline, and you can download an income-and-expense ledger even on the Free plan — exactly the kind of record the flat tax requires for income and receivables.

Official sources

• Financial Administration: Q&A on the flat tax (in Czech)
• Financial Administration: information on the flat tax regime (in Czech)
• Act No. 586/1992 Coll., on Income Tax, Section 7a (in Czech)