Understanding Inbound Webhook Retries in Postmark
This article explains how Postmark handles failed webhook posts for inbound messages and what to expect from our retry system.
💥 What is it?
Postmarkās Inbound Webhook system automatically retries failed webhook posts when your server doesnāt return a 200 OK response.
If all retries fail, the message will appear as an Inbound Error on your Inbound page.
📖 Learn more
👋🏽 How retries work
If Postmark doesnāt receive a 200 OK response from your server, weāll automatically retry sending the webhook.
If we receive a 403 Forbidden response, retries stop immediately.
A total of 10 retries are attempted over roughly 10.5 hours, with increasing intervals between each attempt:
| Retry Interval | Time After Initial Attempt |
|---|---|
| 1st retry | 1 minute |
| 2nd retry | 5 minutes |
| 3rdā5th retries | every 10 minutes |
| 6th retry | 15 minutes |
| 7th retry | 30 minutes |
| 8th retry | 1 hour |
| 9th retry | 2 hours |
| 10th retry | 6 hours |
After all retries are exhausted, the message will be marked as Inbound Error.
āļøImportant notes
The retry schedule cannot currently be customized.
If your webhook endpoint is down for more than ~10.5 hours, those messages may be missed.
You can manually retry a failed inbound message anytime from your Postmark account.