Proforma Invoice for a Sole Proprietorship (JDG) in Poland 2026 — When to Use and How to Issue
Proforma invoice for a sole proprietorship (JDG) in 2026. Differences between a proforma and a VAT invoice, when to issue, template, pitfalls. A practical guide.
A proforma invoice is a document that is not a real invoice — but it is often confused with a VAT invoice. Many sole proprietorships (JDG) use proformas incorrectly, leading to problems with accounting and the tax office.
In this guide I explain what a proforma is, when it is worth using, and what it must contain.
Proforma invoice vs VAT invoice — differences
A proforma invoice is an informational document (an offer) that is not booked. A VAT invoice is an accounting document confirming a sale. You use a proforma before payment, and a VAT invoice after the sale.
Proforma vs VAT invoice — comparison
- ✓The client requests a document before a down payment
- ✓You want to confirm terms before delivery
- ✓Selling to a new business partner (safety)
- ▸Seller and buyer data (NIP, name, address)
- ▸Issue date and payment due date
- ▸Description of goods/services, quantity, unit price
- ▸Gross amount broken down by VAT rate
- ▸Bank account number for the transfer
Important: A proforma is not a tax document — you do not book it in the revenue book or report it in JPK. After receiving payment, you issue a VAT invoice (or advance invoice). You keep the proforma for informational purposes only.
Not sure which document to issue?
Let's check →Information based on art. 2 and art. 106a–106i of the VAT Act (as of 2026). The proforma is not regulated as a separate document in the VAT Act. Market practice indicates its informational nature. This does not constitute tax advice.
What is a proforma invoice?
A proforma invoice is a commercial offer, not an accounting document. It informs the client about the price, conditions, and payment deadline — but it is not a VAT invoice, it is not recorded as revenue, and no VAT is charged on it.
Key differences: proforma vs VAT invoice
- Proforma — an offer, does not generate revenue, does not generate VAT, the client cannot deduct VAT
- VAT invoice — an accounting document, generates revenue and VAT, the client can deduct VAT
- A proforma has no number in the VAT invoice series — it has its own numbering (e.g. PROFORMA/2026/07/001)
When to use a proforma?
1. Advance payment before starting work
Issue a proforma requesting an advance payment. After receiving the payment, you issue an advance invoice.
2. Offer to a client
A proforma is better than a plain offer because it looks like an invoice and contains all accounting data (your NIP (tax identification number), company data).
3. Foreign order
For foreign clients, a proforma helps confirm the terms of the transaction before issuing a VAT invoice, especially for cross-border transactions.
4. Price negotiations
The client may pay after a proforma, but only after negotiating the price. Then you issue a VAT invoice with the final amount.
What should a proforma contain?
A proforma has no statutory requirements (because it is not an invoice), but it should contain:
- The word "PROFORMA" visible on the document
- Proforma number (own numbering)
- Date of issue
- Seller data (name, address, NIP)
- Buyer data (name, address, NIP)
- Description of goods/service
- Quantity, net price, VAT rate, VAT amount, gross
- Payment deadline
- Bank account number
- Fulfilment conditions (when you will perform the service after payment)
Proforma template
PROFORMA no. PROFORMA/2026/07/001
Date of issue: 26.07.2026
Seller:
Jan Kowalski JDG
ul. Przykładowa 1, 00-001 Warszawa
NIP: 1234567890
Buyer:
ABC Sp. z o.o.
ul. Klienta 2, 00-002 Warszawa
NIP: 9876543210
No. | Description | Quantity | Net | VAT | Gross
1 | Programming service | 1 | 5 000,00 zł | 23% | 6 150,00 zł
Total net: 5 000,00 zł
VAT: 1 150,00 zł
Total gross: 6 150,00 zł
Payment deadline: 7 days
Account: 00 0000 0000 0000 0000 0000 0000
Conditions: Fulfilment within 14 days of receiving payment.
Pitfalls
1. A proforma is not a cost invoice
A client who paid against a proforma CANNOT include that amount in their costs. Only after receiving a VAT invoice can they do so.
2. You cannot issue two documents
Do not issue a proforma and then a VAT invoice for the same transaction as a "copy". Issue one proforma, and after payment — one VAT invoice.
3. KSeF and proforma
In KSeF (national e-invoicing system) there is no place for proformas. KSeF only accepts VAT invoices. A proforma remains a commercial document sent outside the system (e.g. by email or PDF).
4. Proforma and the Belka tax
A proforma does not generate revenue, so it does not affect tax. But beware: if a client pays against a proforma and you do not issue a VAT invoice — the tax office may determine that revenue arose anyway (because you received the money).
5. Deadline for issuing an invoice after a proforma
After receiving payment from a proforma, you are obligated to issue a VAT invoice (advance or final):
- Advance invoice: by the 15th day of the month following the month in which the advance was received
- Final invoice: by the 15th day of the month following the month in which the service was performed
FAQ
Can I issue a proforma with VAT, and then an invoice without VAT?
Not recommended. If the proforma contains VAT and the invoice does not — that is an inconsistency. If the service is exempt from VAT, the proforma should also be "zw" (without VAT).
Is a proforma mandatory?
No. A proforma is optional. You can issue a VAT invoice right away. Many sole proprietorships (JDG) do not use proformas at all.
Can a client deduct VAT from a proforma?
Absolutely not. A proforma is not a VAT invoice. VAT can only be deducted from a VAT invoice (or an advance invoice).
Does a proforma need an NIP?
Not required, but recommended. Without an NIP, the client may not know this is a business document.
Need help with invoices?
Oxyok accounting — from 49 zł + VAT per month. We will help you determine when to issue proformas, advance invoices, and VAT invoices, and ensure KSeF works correctly.
Write to: [email protected]
Disclaimer: This article is informational in nature — before making a decision, consult an accountant.
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