KSeF Poland Guide

Introduction

On June 30, 2025, Poland’s Ministry of Finance released KSeF 2.0. This update includes the publication of the FA(3) Schema, the API 2.0 documentation and supporting materials. FA(3) will become mandatory for large taxpayers on February 2026 and will roll out for other taxpayers on April 2026. Invopop will help you meet these deadlines, get in touch with us.

KSeF (Krajowy System e-Faktur) is Poland’s official national platform for electronic invoicing, established and operated by the Ministry of Finance. KSeF with the FA_VAT format aim to increase transparency, streamline VAT compliance, and reduce tax fraud in business-to-business (B2B) invoicing. Invoices are encoded in FA_VAT, a strict XML format published and maintained by Polish tax authorities. The schema enforces standardized fields for both domestic and cross-border transactions, including buyer/seller data, VAT details, and item lines. The KSeF system performs real-time validation of all submitted invoices, checking against the schema and business rules. Validated invoices receive a unique KSeF ID and official ‘receipt’ timestamp. The platform provides secure archiving for issued and received e-invoices. Parties can access, verify, and download invoices using authentication methods prescribed by Polish law, such as qualified electronic signatures, trusted profiles, or dedicated system tokens. KSeF ensures strict regulatory compliance, including requirements for data protection, digital signatures, and audit trails, aligned with Polish and EU laws.

Pre-requisites

This guide assumes that you have a Company NIP and an account in Poland’s National System e-Invoices (KSeF). You require an issuer token for each environment, obtained at the KSeF portal (Test | Production).

Generate a token with 'issuing invoices' permissions

Setup

Connect the KSeF Poland app

Navigate to Configuration → Apps
Locate KSeF Poland in the app discovery list
Tap Connect to activate

The initial connection requires no configuration for sending invoices.

Configure sending workflow

KSeF send invoice workflow

Signs and converts the GOBL document into the FA_VAT XML format and then sends it to KSeF.

Make sure you configure the Send to KSeF step with your Issuer NIP and the Issuer Token generated in the KSeF Portal.

Send an Invoice

The following examples are of partial GOBL documents you can copy and paste directly into the Invopop Console or store via the API as silo entries. GOBL Invoices sent to KSeF require the following properties in order to perform the correct normalization and validation steps. Invopop will try to assign these automatically, but we recommend defining them explicitly before upload:

$regime to be set to PL

Self-billed invoice (KSeF)

KSeF self-billed invoice

{
    "$schema": "https://gobl.org/draft-0/bill/invoice",
    "$regime": "PL",
    "$tags": [
        "self-billed"
    ],
    "uuid": "3aea7b56-59d8-4beb-90bd-f8f280d852a0",
    "type": "standard",
    "code": "SAMPLE-001",
    "issue_date": "2025-08-01",
    "currency": "PLN",
    "supplier": {
        "name": "Provide One S.L.",
        "tax_id": {
            "country": "PL",
            "code": "9876543210"
        },
        "addresses": [
            {
                "num": "42",
                "street": "ul. Przykładowa",
                "locality": "Warszawa",
                "region": "mazowieckie",
                "code": "00-015",
                "country": "PL"
            }
        ],
        "emails": [
            {
                "addr": "billing@example.com"
            }
        ]
    },
    "customer": {
        "name": "Your Company S.A.",
        "tax_id": {
            "country": "PL",
            "code": "1234567788"
        },
        "addresses": [
            {
                "num": "43",
                "street": "ul. Przykładowa",
                "locality": "Warszawa",
                "region": "mazowieckie",
                "code": "00-015",
                "country": "PL"
            }
        ]
    },
    "lines": [
        {
            "i": 1,
            "quantity": "20",
            "item": {
                "name": "Development services",
                "price": "90.00",
                "unit": "h"
            },
            "sum": "1800.00",
            "taxes": [
                {
                    "cat": "VAT",
                    "rate": "standard",
                    "percent": "23.0%"
                }
            ],
            "total": "1800.00"
        },
        {
            "i": 2,
            "quantity": "1",
            "item": {
                "name": "Financial service",
                "price": "10.00",
                "unit": "service"
            },
            "sum": "10.00",
            "taxes": [
                {
                    "cat": "VAT",
                    "rate": "reduced",
                    "percent": "8.0%"
                }
            ],
            "total": "10.00"
        }
    ]
}

FAQ

Please contact the Invopop support team if you have any questions that are not listed here.

What types of invoices are supported in Invopop's KSeF Integration?

I don't have presence in Poland in order to obtain an Issuer NIP or Token

Getting Started

Use Cases

Feature Guides

Country Guides

Integrations

KSeF Poland Guide

Introduction

Pre-requisites

Setup

KSeF send invoice workflow

Send an Invoice

FAQ

Getting Started

Use Cases

Feature Guides

Country Guides

Integrations

​Introduction

​Pre-requisites

​Setup

KSeF send invoice workflow

​Send an Invoice

​FAQ

Introduction

Pre-requisites

Setup

Send an Invoice

FAQ