One of the first practical questions after you register as an OSVČ — a self-employed person (sole trader) in Czechia — is how to issue invoices. Most people reach for a spreadsheet, and the reasoning is sound: you already know Excel or Google Sheets, it is already on the computer, and a downloaded template turns into an invoice in ten minutes. What works for the first three invoices stops working somewhere around the thirtieth. This article goes through what a spreadsheet cannot do for you, which signals mean it is time to move, and how the move actually works.
Why sole traders start in a spreadsheet
None of the reasons are bad ones. For the first few invoices a spreadsheet is a perfectly reasonable answer:
- It costs nothing — you already have Excel or Google Sheets and pay nothing on top
- You already know it — almost everyone can find their way around a table
- It bends to you — the invoice can look exactly the way you want it to
- It starts immediately — no sign-up, no configuration
The trouble starts when the business grows, and it usually grows sooner than you expect.
Ten things a spreadsheet will not do for you
1. Number the invoices
Section 29(1)(e) of the VAT Act requires a tax document to carry a number that identifies it uniquely. If you are not registered for VAT the requirement reaches you from a different direction: Section 7b of the Income Tax Act says your tax records (daňová evidence) must be complete and provable, and a series with two invoices sharing a number is neither. The Accounting Act does not apply to you at all while you keep tax records rather than double-entry books. In a spreadsheet, keeping the series straight is entirely your job — one copied row and the same number goes out twice. Invoicing software assigns the next number itself and flags a number you typed that already exists on another invoice for the same client.
2. Work out the VAT
If you are registered for VAT, the invoice has to state the tax base, the rate and the tax for each line. You can build the formulas in a spreadsheet, but a rewritten cell or a row pasted below the last one the formula covers breaks them silently. With more than one rate on a single invoice — 21 %, 12 % and 0 % are the rates a Czech VAT payer works with — the table gets hard to read. Invoicing software calculates the VAT as you type and prints the recapitulation by rate.
3. Put a payment QR code on the invoice
A QR payment code (QR Platba) is standard in Czechia. The client scans it in their banking app and the account number, amount and variable symbol fill themselves in, so there is nothing left to mistype. A spreadsheet will not generate one: you would need an external generator, an image pasted into the sheet, and the same routine repeated on every invoice. In Taxorio, once QR payments are switched on, the code is added to every invoice with a positive amount.
4. Produce the XML the Financial Administration expects
A VAT payer files the VAT return (DPHDP3), the VAT control statement (DPHKH1) and, where EU supplies are involved, the EC Sales List (DPHSHV) — all electronically, in XML. A spreadsheet gives you no XML, so the figures have to be retyped into the form on the Financial Administration portal. Taxorio generates the XML files (DPHDP3, DPHKH1, DPHSHV and DPFDP7 for the personal income tax return) from the invoices and expenses already recorded; the XML exports belong to the PRO plan.
5. Tell you where you stand right now
How much have you invoiced this year? How much of it is overdue? What is the ratio of income to expenses? In a spreadsheet those answers come from pivot tables and charts that you build and then keep refreshing by hand. The overview in Taxorio shows income and expenses by month, and what is outstanding, without you maintaining anything.
6. Catch a human mistake
A spreadsheet has nothing to check you against. An overwritten formula, a row left outside the sum, a copied line that still carries last year's rate — none of it announces itself. On an invoice that turns into the wrong tax, the wrong variable symbol or the wrong total, and you usually find out from the client or from the tax office rather than from the file.
7. Check that the invoice has everything the law asks for
Section 29 of the VAT Act lists what a tax document must contain: the identification of supplier and customer, the DIČ (tax ID), the DUZP (date of taxable supply), the tax base, the rate and the tax. In a spreadsheet all of that rests on your memory. An invoicing form asks for the mandatory fields and will not save the document while they are missing. It does not replace your own judgement about what you are billing for, but it does stop the ordinary omissions.
8. Produce a PDF that holds its shape
You normally send the invoice as a PDF. Excel does export to PDF, but the result is unpredictable: split tables, clipped text, page breaks in the wrong place. In Taxorio the PDF is one click and comes out with your logo, the QR code and the full recapitulation, in one of several templates — Aurora, Modern or Classic.
9. Remember your clients
In a spreadsheet you retype the client's name, IČO (business ID), DIČ and address on every invoice. Or you build a second sheet and link it with lookups, which is one more layer to maintain and one more place to break. Invoicing software stores the client once. Taxorio fills the record from the ARES business register: you enter the IČO and it returns the name, address, DIČ and whether the client is registered for VAT.
10. Read a supplier document for you
As a sole trader you also receive invoices and need to record the expense side. In a spreadsheet every document is retyped by hand. Taxorio reads the document instead — photograph a receipt or upload a supplier PDF and it pre-fills the category, the amount, the date and the supplier, leaving you to check what it recognised.
When it is time to leave the spreadsheet
A few signals are fairly reliable.
The client list is growing
Past roughly five clients a month, the spreadsheet starts costing more than it saves. Each invoice takes longer than it should and there are more places for a mistake to hide.
You are becoming a VAT payer
This is the strongest reason of the lot. Once your turnover passes CZK 2,000,000 in a calendar year — or you register voluntarily — you file VAT returns and control statements on a fixed rhythm. Doing that out of a spreadsheet is laborious and easy to get wrong.
You need to see the numbers
If you catch yourself building reports and charts instead of doing the work clients pay for, the reporting should be automatic.
You want the invoice to look the part
The invoice is often the only document a client keeps from you. A spreadsheet with broken formatting says something about how you work; a clean PDF with a logo, a QR code and a structured recapitulation says something else.
A tax inspection is possible
The tax office can open an inspection at any time, as a rule covering the last three years. If the invoices are spread across dozens of spreadsheet files with no systematic record, that gets painful. Invoicing software keeps everything in one place.
What invoicing software adds
Collected in one list, this is what a spreadsheet does not give you:
- Automatic invoice numbering with no gaps or repeats
- QR payment codes generated on the invoice itself
- An ARES lookup that fills in the client's details from the IČO
- VAT calculation with the recapitulation by rate
- XML exports for the VAT return, the control statement, the EC Sales List and the income tax return
- A financial overview of income, expenses and outstanding invoices
- Document recognition for supplier invoices and receipts
- A client database with the invoice history attached
- PDF templates that hold their layout
- Invoices in six currencies — CZK, EUR, USD, GBP, CHF and PLN
- Copying an invoice for work that repeats
What the switch costs
Less than most people assume. Taxorio's FREE plan covers 2 invoices, 5 expenses and 5 AI document recognitions a month, which is enough to find out whether the tool suits the way you work. PRO costs CZK 69 a month, removes the limits on invoices and expenses, raises document recognition to 150 a month and unlocks the XML exports.
Weigh that against the time the spreadsheet takes. How many extra hours a month it costs you is something only you can estimate — multiply the estimate by your own hourly rate and compare it with the subscription. That is the only number the decision really turns on.
How to move over
The move is not a project. Six steps cover it:
- Sign up — an e-mail address or a Google account is enough.
- Fill in your business details — IČO, DIČ, address, bank account. They then appear on every invoice automatically.
- Add your clients — enter the IČO and the ARES lookup completes the rest.
- Set the counter — the number format is fixed as YYYYXXXX, and in the settings you choose the number the series continues from, so the first Taxorio invoice follows on from the last one you issued in the spreadsheet. On an individual invoice you can still type a number of your own.
- Save the items you bill repeatedly — a price list entry carries its description, price and VAT rate, so recurring work is picked from a list instead of retyped.
- Issue the first invoice — and compare it with what the spreadsheet produced.
One thing worth saying plainly: there is no need to re-enter the old invoices. Keep them archived in the original files and start the new records from the current date.
Excel has its place — just not in invoicing
Excel is an excellent tool for analysis, calculations and one-off tables. It was never designed for a numbered series of tax documents, an expense ledger and filings with statutory deadlines. The longer the invoicing stays there, the more of your time it quietly takes.
If you are still weighing up the options, this comparison of invoicing software for Czech sole traders lays the alternatives side by side.
Taxorio scope: Taxorio provides invoicing and income/expense records for Czech sole traders. It is not full accounting or personalised tax advice. For an unsupported or unusual case, verify the treatment with a Czech accountant or tax adviser before filing.