IPN messages
💵 Invoice payment status updates
There is an option for the web store (or other business application) to receive notifications about the payment status of an invoice via IPN (Instant Payment Notification).
This message is sent by Számlázz.hu to the specified web address as an HTTP POST request. The URL can be specified within the billing account on the Fiók beállítások / Számlázás alapadatok page.
The detailed IPN description is available in the Számlázz.hu knowledge base.
⏰ When is the IPN message sent?
The IPN message is created when:
- An invoice's paid amount changes (e.g., partial or full payment occurs)
- The change occurs on the invoice issuer's side
- The company has a configured IPN URL
📋 IPN message parameters
The IPN message contains the following parameters:
| Parameter | Description | Example |
|---|---|---|
szlahu_szamlaszam | The settled invoice number | E-2020-123 |
szlahu_dijbekero_szama | The parent pro forma invoice number (if any) | DB-2020-456 |
szlahu_rendelesszam | Order number (if included on invoice) | RND1234 |
szlahu_bruttovegosszeg | The gross total amount of the invoice | 10000 |
szlahu_kifizetettbrutto | The paid amount | 10000 |
szlahu_fizetesmod | The payment method | kp, bankkártya, átutalás |
szlahu_kifizdat | The payment date (YYYY-MM-DD) | 2025-05-14 |
The szlahu_kifizdat IPN message is not activated by default. If you wish to utilize this feature, our customer service team will be happy to assist you in setting it up. Please contact our customer service representatives!
💻 Technical implementation
IPN message format
IMPORTANT: IPN message data is sent in the HTTP POST request body. The message arrives with application/x-www-form-urlencoded content type.
Response requirement
The receiving system must send an HTTP 200 OK response to indicate successful processing. The response body content is not relevant, only the HTTP status code matters.
⚠️ Important notes
Retry mechanism
If IPN sending fails (no 200 OK response is received, or a timeout occurs), the system automatically retries sending. The retry mechanism works as follows:
- IPN messages are not sent immediately
- We attempt to send payment information every 3 minutes
- Maximum 10 attempts are made
- If we don't receive an HTTP 200 OK response, the IPN is discarded
IPN message accumulation
IPN requests may accumulate in the sending system (Számlázz.hu), especially during high traffic. These messages are automatically sent to the receiving system over time.
Duplicate message handling
The system ensures that only one active IPN message exists per invoice at a time. If multiple IPN records belong to an invoice, only the latest one is sent, and the others are automatically deleted.
🌐 IP addresses and network settings
IPN messages are sent from the following IP addresses:
3.73.214.98
3.76.149.232
18.153.156.51
If you use IP-based filtering, add these addresses to your whitelist.
The previous IP addresses (18.153.1.171, 3.73.114.72, 52.59.28.5) are no longer used from August 1, 2025.
Detailed information: Technological changes 2025