Introducing the PUQ KSeF Integrator WHMCS Addon

A powerful addon designed for WHMCS users operating in Poland (and EU/international scenarios) who need reliable integration with KSeF (Krajowy System e-Faktur) maintained by the Polish Ministry of Finance. This addon automates the full lifecycle of KSeF e-invoices — from XML generation to secure transmission, status tracking, and confirmation documents.

https://doc.puq.info/books/ksef-integrator-whmcs-addon

Limited Time Offer: €50 Discount on the Annual Plan

For a limited time, we’re offering a €50 discount when you choose the annual billing cycle for the PUQ KSeF Integrator WHMCS Addon.

To activate the discount, enter the promo code "KSeF" during checkout — the €50 discount will be applied to your yearly order automatically.

Promo code: KSeF Applies to: Annual plan only Discount: €50 off per year

All-in-One KSeF Automation for WHMCS

PUQ KSeF Integrator eliminates manual steps and risky “semi-automation”. Once an invoice is paid in WHMCS, the addon can automatically prepare, validate, generate FA(3) XML, send it to KSeF, then retrieve and store all the official results back in WHMCS.

Secure Communication & Compliance-Oriented Processing

The addon follows the official KSeF flow, including XAdES authentication, secure session handling, and encrypted invoice transmission. It also validates key accounting rules (like supported VAT rates) before sending.

Flexible Workflows + Clear Visibility in WHMCS

You get dedicated UI tools inside WHMCS: invoice lists, KSeF status panel directly on the invoice page, a dashboard widget, and detailed debug logs for troubleshooting.

Main Features

• Automatic invoice sending to KSeF — after a WHMCS invoice becomes Paid, the addon triggers processing via the InvoicePaid hook and sends the FA(3) XML to KSeF.

• FA(3 format compliance — generates structured e-Invoices in the FA(3) format required by KSeF.

• Credit balance compensation support — correctly processes invoices paid fully or partially using WHMCS client credit (balance compensation).

• Automatic retrieval of KSeF number and UPO — after acceptance, the addon downloads the official confirmation (UPO) and assigns the KSeF number to the invoice record.

• KSeF QR code on PDF invoices — generates a KSeF verification URL + QR code and lets you embed it into your WHMCS PDF invoice template.

• Test & Production environments — supports both KSeF environments with separate certificates:

  • Test: https://ksef-test.mf.gov.pl and https://qr-test.ksef.mf.gov.pl
  • Production: https://ksef.mf.gov.pl and https://qr.ksef.mf.gov.pl

• Detailed API communication logging — debug mode logs each step directly in WHMCS for fast diagnostics.

• Multi-currency support — automatic currency conversion logic for invoices issued in foreign currencies.

• Invoice statuses & queue control — clear statuses for every invoice: pending, processing, accepted, rejected, error.

• KSeF panel on the invoice page — KSeF data displayed directly on the WHMCS admin invoice page.

• Dashboard widget — KSeF invoice statistics and visibility on the WHMCS admin home page.

• Certificate management (XAdES) — secure storage of certificates with encryption.

• Multilingual interface — Polish and English UI.

How It Works

1. WHMCS invoice gets status Paid → InvoicePaid hook starts the process.
2. The addon collects invoice, client, and seller data and validates required values.
3. VAT rates are validated (supported rates include: 0, 3, 4, 5, 7, 8, 22, 23%).
4. The addon generates FA(3) XML.
5. Secure KSeF session flow is executed (XAdES auth, encryption, transmission).
6. The addon checks KSeF processing status (multiple attempts).
7. After acceptance: KSeF number, UPO, and QR verification link are saved to WHMCS.

License

The PUQ KSeF Integrator addon requires an active license for full functionality. The license is verified via PUQ Cloud license server and the result is cached (so the addon does not require a constant connection).

Without an active license, the addon works in limited mode:

• Invoices can still be collected into the queue as pending after payment
• Viewing invoice data, statistics, XML preview, UPO download, environment check, and dashboard widget remain available
• Sending to KSeF, resending, auto-send, configuration saving, and certificate management are restricted (UI shows warnings)

Module Documentation

https://doc.puq.info/books/ksef-integrator-whmcs-addon