> ## Documentation Index
> Fetch the complete documentation index at: https://docs.invopop.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Poland FAQ

> Frequently asked questions about invoicing compliance in Poland

### Compliance questions

<AccordionGroup>
  <Accordion title="When does mandatory KSeF invoicing start in Poland?">
    1 February 2026 for taxpayers with turnover above PLN 200M and 1 April 2026 for everyone else (large/medium businesses) — schedule confirmed by Sejm in mid-2024 after delays. B2C is optional. Foreign-only businesses without a fixed Polish establishment are out of scope.
  </Accordion>

  <Accordion title="Who can act as a supplier in Poland?">
    Any entity with a Polish NIP and active KSeF access. Large taxpayers (turnover > PLN 200M) must be onboarded by 1 February 2026; the rest by 1 April 2026. Foreign-only entities without a Polish fixed establishment cannot use KSeF.
  </Accordion>

  <Accordion title="What are the legal obligations for receiving invoices in Poland?">
    Once KSeF is mandatory, all B2B invoices must be received through KSeF — paper or PDF rejection is no longer permitted between Polish parties. Archival is automatic in KSeF for 10 years; recipients can pull copies at any time.
  </Accordion>

  <Accordion title="What periodic reporting obligations exist in Poland?">
    JPK\_V7M (monthly) or JPK\_V7K (quarterly) consolidated VAT and SAF-T file. Once KSeF is mandatory, JPK\_V7 is expected to draw directly from KSeF data, eliminating manual reconciliation.
  </Accordion>

  <Accordion title="What types of invoices are supported in Invopop's KSeF integration?">
    Currently supported invoice types:

    * **Standard Invoices (FAT)**: Regular B2B invoices with FA(3) schema
    * **Credit Notes (KOR)**: Invoice corrections and adjustments

    All invoices must include the `pl-favat-v3` addon in GOBL to ensure FA(3) schema compliance.

    <Note>
      Additional invoice types can be supported based on customer requirements. Contact [support](mailto:support@invopop.com) if you need specific invoice types.
    </Note>
  </Accordion>

  <Accordion title="Will B2C transactions need to be reported in KSeF?">
    No. B2C invoices in KSeF are optional. The mandatory requirement applies only to B2B transactions.
  </Accordion>

  <Accordion title="Are there special supplier obligations under KSeF?">
    The KSeF certificate must belong to the company account directly or to a user with both InvoiceRead and InvoiceWrite permissions in KSeF. Suppliers must declare KSeF as their issuer in the Ministry of Finance taxpayer's portal before going live.
  </Accordion>

  <Accordion title="What are the legal obligations for receiving invoices through KSeF?">
    Once KSeF is mandatory, all Polish B2B recipients must accept KSeF-issued invoices. KSeF itself archives for 10 years; recipients have no separate archival duty for the structured XML.
  </Accordion>
</AccordionGroup>

### Invoicing questions

<AccordionGroup>
  <Accordion title="What happens when I send an invoice to a foreign recipient?">
    International (cross-border) invoices are handled just like domestic invoices in KSeF:

    * The invoice is created in GOBL with the foreign recipient's details
    * It's converted to FA(3) XML format and submitted to KSeF
    * KSeF validates and clears the invoice, assigning a unique KSeF ID
    * The invoice is registered in the KSeF system

    However, since foreign recipients cannot access KSeF, you must deliver the invoice through other channels (email, EDI, etc.). Include the KSeF QR code in the delivery for verification purposes.
  </Accordion>

  <Accordion title="What's the difference between test, demo, and production environments?">
    **Test mode** (sandbox only): Uses self-signed certificates generated automatically by Invopop. Perfect for quick testing without accessing the KSeF portal. Invoices are not sent to real KSeF servers.

    **Demo mode** (sandbox only): Connects to the official [KSeF Demo Portal](https://ap-demo.ksef.mf.gov.pl/web/). Requires manual certificate generation, simulating the full production flow in a safe test environment.

    **Production mode** (live workspace): Connects to the live [KSeF Portal](https://ap.ksef.mf.gov.pl/). Requires valid company credentials and certificates. All invoices are submitted to the official KSeF system.

    <Tip>
      Use test mode for initial integration testing, then switch to demo mode when you're ready to simulate the real certificate flow before going live.
    </Tip>
  </Accordion>

  <Accordion title="What KSeF applications and portals are available?">
    Official KSeF applications:

    * [KSeF Taxpayer Application](https://ksef.podatki.gov.pl/aplikacja-podatnika-ksef-i-inne-narzedzia/bezplatne-narzedzie-wersja-produkcyjna/) – the main portal with all functionalities
    * [KSeF Mobile Application](https://ksef.podatki.gov.pl/aplikacja-podatnika-ksef-i-inne-narzedzia/aplikacja-mobilna-ksef/) – a mobile app for on-the-go access
    * [e-mikrofirma](https://login.mf.gov.pl/Account/Select?ReturnUrl=%2Fconnect%2Fauthorize%2Fcallback%3Fclient_id%3D09e2877e-702a-4e27-8818-9472ca964c0a%26redirect_uri%3Dhttps%253A%252F%252Furzadskarbowy.gov.pl%26response_type%3Dcode%26scope%3Dprofile%2520openid%2520DataHub.UserAccess%2520eFormsClientApi.UserAccess%2520ChatApi.UserAccess%2520offline_access%26state%3D8f196c7682654d0da49b42bfc9045e51%26code_challenge%3DSIwxyxXJpAzUgzrMW96UIH9vNc6P0-dkdc7l482AWQA%26code_challenge_method%3DS256) – a simplified portal aimed at micro-entrepreneurs

    For testing:

    * [KSeF Demo Portal](https://ap-demo.ksef.mf.gov.pl/web/) – demo environment for testing
  </Accordion>

  <Accordion title="How do I configure my workspace for Polish invoicing?">
    Install the KSeF Poland app, register your supplier (Test, Demo, or Production environment), and run invoices through the Send Invoice workflow. Each environment requires its own NIP and certificate setup.
  </Accordion>

  <Accordion title="I get a &#x22;failed to create session (Status 403 Forbidden)&#x22; error when sending an invoice to KSeF. What does it mean?">
    This error means the uploaded KSeF certificate does not have the required permissions to issue invoices. This typically happens when the certificate was uploaded by someone who is not the company administrator and only has limited permissions granted by the main company account.

    The KSeF certificate uploaded to Invopop must belong to either:

    * The **company account** directly logged into KSeF, or
    * An entity that has both **InvoiceRead** and **InvoiceWrite** permissions (managed within KSeF)

    To resolve this, you have two options:

    1. **Grant permissions in KSeF**: The company admin (or whoever has direct access to the KSeF company account) grants `InvoiceRead` and `InvoiceWrite` permissions to the user who uploaded the certificate to Invopop. This can be done from the [KSeF application portal](https://ap.ksef.mf.gov.pl/) and requires no further action in Invopop (no need to unregister/register).
    2. **Re-register with a new certificate**: Unregister the supplier in Invopop and register it again using a certificate generated from the main KSeF company account (or another account with the required permissions).
  </Accordion>

  <Accordion title="Where do I find Poland-specific GOBL documentation?">
    See the [Poland tax regime in GOBL](https://docs.gobl.org/regimes/pl) for tax categories and NIP rules. The [`pl-favat-v3`](https://docs.gobl.org/addons/pl-favat-v3) addon documents the FA(3) schema fields required for KSeF.
  </Accordion>

  <Accordion title="How do I set the unit of measure (jednostka miary) on a line item, like &#x22;szt.&#x22; or &#x22;usł.&#x22;?">
    Polish invoicing law requires a unit of measure for every line, and KSeF maps it to the `P_8A` field on each `FaWiersz`. Invopop supports two ways to populate it:

    1. **Canonical unit code on `Item.Unit`** — preferred when the unit exists in the GOBL unit catalogue or as a UN/ECE Recommendation 20 code. For example, `Item.Unit: "H87"` (piece) or `Item.Unit: "KGM"` (kilogram). The gobl.ksef converter emits the UN/ECE code directly into `P_8A`.
    2. **Free-form label on `Item.Meta["unit-label"]`** — use this for Polish abbreviations that do not match a canonical code, such as `"szt."` (sztuka — piece), `"usł."` (usługa — service), `"kpl."` (komplet — set) or `"opak."` (opakowanie — package). The value is passed through to `P_8A` unchanged, so the supplier's exact wording is preserved on the KSeF XML.

    Example line item using a free-form label:

    ```json theme={"system"}
    {
      "item": {
        "name": "Konsultacja prawna",
        "price": "200.00",
        "meta": {
          "unit-label": "usł."
        }
      },
      "quantity": "1"
    }
    ```

    <Note>
      When an inbound KSeF invoice contains a `P_8A` value that is not a recognised GOBL or UN/ECE code, gobl.ksef preserves the original string under `Item.Meta["unit-label"]` so round-trips do not lose the supplier's wording. `Item.Unit` is only populated when the value validates as a canonical code.
    </Note>
  </Accordion>
</AccordionGroup>

### Registering supplier questions

<AccordionGroup>
  <Accordion title="Why did my supplier registration fail?">
    Common reasons for registration failures:

    * **Certificate and private key mismatch**: Ensure you uploaded both files from the same certificate generation
    * **Incorrect password**: Verify the password matches what you set during certificate generation
    * **Future start date**: Certificate start date must be today or in the past
    * **Wrong portal environment**: Demo certificates won't work with production, and vice versa
    * **File encoding issues**: For API uploads, ensure files are properly base64-encoded
    * **Expired certificate**: Check that the certificate is still valid
    * **Invalid NIP**: Verify the Polish Tax ID is correct and has access to KSeF

    <Note>
      Check the workflow error logs in the Invopop Console for detailed error messages that can help diagnose the specific issue.
    </Note>
  </Accordion>

  <Accordion title="I don't have a Polish NIP for testing. How can I get one?">
    **For sandbox testing**:

    * **Test mode**: Generate fake NIPs at [http://generatory.it/](http://generatory.it/). These work immediately with self-signed certificates.
    * **Demo mode**: You need a real NIP with access to the KSeF Demo Portal.
  </Accordion>

  <Accordion title="How do I onboard a new supplier in Poland?">
    Choose an environment (Test, Demo, or Production). Generate a KSeF certificate from the relevant portal (or use a self-signed cert in Test mode), upload it to Invopop with the matching password, and register the supplier through the KSeF Register Supplier workflow.
  </Accordion>

  <Accordion title="What certificates does KSeF require to authenticate a supplier?">
    A KSeF certificate exported as PKCS#12 (.p12) with password, generated through the KSeF Application Portal (or auto-generated by Invopop in Test mode). The certificate must have InvoiceRead + InvoiceWrite permissions.
  </Accordion>

  <Accordion title="How are supplier credentials stored in Invopop for Poland?">
    The KSeF certificate (PKCS#12 .p12 with password) is stored encrypted at rest. Invopop uses it to authenticate session creation with KSeF on the supplier's behalf; the password is never returned in API responses.
  </Accordion>
</AccordionGroup>

### Receiving questions

<AccordionGroup>
  <Accordion title="How do I import received invoices from suppliers?">
    Invopop automatically imports received invoices through a polling service:

    1. **Configure polling interval** during party registration (hourly, daily, weekly, or monthly)
    2. **Set up the sync workflow** to query KSeF for new invoices
    3. **Configure the import workflow** to convert FA(3) XML to GOBL format
    4. **Link the workflows** in the Poland app configuration

    The system automatically checks KSeF at your chosen interval and imports any new invoices to your configured folder.

    **For manual import**, use the API to trigger import jobs with specific KSeF numbers or date ranges. See the [Import Received Invoices](/guides/pl-ksef#import-received-invoices) section in the guide.
  </Accordion>

  <Accordion title="Can I import historical invoices or backfill missed invoices?">
    Yes. You can manually trigger a sync workflow to import invoices from a specific date range using the [Create a Job endpoint](/api-ref/transform/jobs/create-a-job-post).

    Pass the `from` and `upto` date parameters to sync all invoices received within that period:

    ```json theme={"system"}
    {
      "workflow_id": "YOUR_SYNC_WORKFLOW_ID",
      "entry_id": "YOUR_PARTY_ENTRY_ID",
      "args": {
        "from": "2026-01-01T00:00:00Z",
        "upto": "2026-01-31T23:59:59Z"
      }
    }
    ```

    This is useful for backfilling invoices after a polling outage or importing historical data before enabling automatic polling.
  </Accordion>

  <Accordion title="How do I know if my automatic invoice import is working?">
    Check these indicators:

    1. **Polling configuration**: Verify the polling interval is set in your party registration workflow configuration
    2. **App configuration**: Confirm the Poland app has your sync workflow configured
    3. **Recent imports**: Check the "Invoices · Expenses" folder for newly imported invoices
    4. **Job logs**: Review job logs in the Console for sync and import workflow executions
    5. **Error notifications**: Set up email or Slack notifications in your workflow error handling to alert you of failures

    <Tip>
      Test the import by manually triggering the sync workflow with a date range that includes known received invoices.
    </Tip>
  </Accordion>

  <Accordion title="What format do received KSeF invoices arrive in?">
    FA(3) XML conforming to the Ministry of Finance schema. Each invoice carries a unique KSeF reference (numer KSeF) plus the issuer's signature and a QR code linking to the public verification page.
  </Accordion>

  <Accordion title="How does Invopop convert received Polish invoices into GOBL?">
    Inbound FA(3) XMLs are parsed via [`gobl.favat`](https://github.com/invopop/gobl). Tax rates, line items, and parties map onto GOBL fields; the original signed XML is preserved as a silo entry attachment.
  </Accordion>
</AccordionGroup>

***

<Card title="Participate in our community" icon="forumbee" href="https://community.invopop.com" arrow="true" horizontal>
  Ask and answer questions about Poland's regulation →
</Card>