Retries

Fern automatically retries webhook deliveries if your server does not respond with a 2xx HTTP status code.

Retry Policy

Each webhook event will be attempted up to 4 times total (1 initial + 3 retries) using an exponential backoff strategy:

Attempt	Delay Before Retry
1st	Immediate (no delay)
2nd	5 seconds
3rd	30 seconds
4th	1 minute

If all attempts fail (i.e., your endpoint continues to return a non-2xx response or times out), the webhook will be marked as undelivered and no further attempts will be made.

We recommend that your webhook handlers are idempotent and respond quickly (within 5 seconds). To ensure reliability, log incoming webhook ids (from the payload id ) and avoid side effects on duplicate deliveries.