---
title: "Inbound Email Webhooks: Design Patterns and Safety | SendHQ"
description: Use webhooks to process inbound messages without building a polling mailbox workflow.
canonical: https://sendhq.cc/guides/inbound-email-webhooks
last-updated: 2026-08-24
---
# Inbound Email Webhooks: Design Patterns and Safety

Use webhooks to process inbound messages without building a polling mailbox workflow.

An inbound-email webhook delivers a structured event to your application when a message arrives. The design challenge is safe parsing, authentication, idempotency, and handling retries without losing messages.

## What this means in practice

- Signed or authenticated webhook delivery
- Message IDs for idempotent processing
- Raw-message retention for recovery
- Async handling for attachments and downstream work

## Implementation checklist

1. Validate the webhook source before parsing content.
2. Persist the provider message ID before side effects.
3. Queue long-running attachment or AI processing.
4. Return a success response quickly and retry safely on transient failures.

## Questions teams ask

**Should I process attachments inside the webhook request?**

Usually no. Persist the message and enqueue attachment work so acknowledgement remains fast and retry-safe.

**How do I handle duplicate webhooks?**

Treat the provider message ID as unique and make downstream operations idempotent.

## Continue learning

- [Email API: Send, Receive, and Track Transactional Email](https://sendhq.cc/guides/email-api.md): Understand what an email API does, how sending and inbound receiving work, and what to evaluate before choosing one.
- [Transactional Email API Guide](https://sendhq.cc/guides/transactional-email-api.md): A practical guide to sending passwords, receipts, alerts, and other product-triggered email reliably.
- [How to Send Email with an API](https://sendhq.cc/guides/send-email-with-api.md): A step-by-step approach to authenticated API email sending, testing, and production safety.
- [How to Receive Email with an API](https://sendhq.cc/guides/receive-email-with-api.md): Route inbound mail to your application, parse it safely, and make it useful in a product workflow.
- [Email Domain Verification: SPF, DKIM, and DMARC](https://sendhq.cc/guides/email-domain-verification.md): What domain verification is, why it matters, and how SPF, DKIM, and DMARC work together.