Behind the Growth Stack: Multi-Channel Unsubscribe Automation with Braze

Written by Valentina Llanos Pontaut
(Solutions Architect) 

Manual unsubscribes were failing. Users who opted out of communications were still receiving messages across WhatsApp, email, and push — creating compliance risks and damaging trust. In this post, we’ll show how we solved that with multi-channel unsubscribe automation, using Braze’s APIs to build a scalable, centralized opt-out engine that eliminated manual errors and saved operations hours of time.

🚨 When “Stop” Doesn’t Stop

Both for WhatsApp and for email/push channels, the challenge was the same:

• Teams handled unsubscribes manually inside Braze profiles.

• As a result, some users were mistakenly resubscribed, received unwanted notifications, and lost trust.

• We hypothesized that automating unsubscriptions via API and centralizing the process would reduce human error, protect user experience, and save operational time.

⚙️ Building the Auto-Unsubscribe Engine

We created a multi-channel automation to unsubscribe unwanted users through Braze’s users/track endpoint. The approach had three core components.

🎯 Step One: Who Needs to Be Blocked?

We used two methods for both WhatsApp and email/push:

• User property flag: Adding a “blocked” property in the user profile. This method automates targeting, although it consumes a data point when updated.

• CSV upload: Uploading a list of external_ids. This method avoids data point consumption, but it requires manual CSV uploads.

Therefore, each client can choose the method that best fits their workflow.

🔗 Step Two: Webhooks to the Rescue

• Webhook campaign: Built in Braze using users/track endpoint.

• Headers:

  • Content-Type: application/json
  • Authorization: Bearer <REST API Key> (must have users.track permissions).

WhatsApp request body:

Email + Push request body:

Cluster endpoint:

https://rest.iad-0X.braze.com/users/track (replace X with cluster number).

⏱ Step Three: Set It and Forget It

• Schedule: Send as soon as the campaign launches.

• Delivery Controls: Allow re-eligibility every 15 minutes. This ensures the system reprocesses edge cases where users reappear as subscribed.

• Target audience: Segment of blocked or unwanted users (via property or CSV).

• Important: Remove the control group in A/B Testing.

🌊 What Changed When Automation Took Over

• Impact: The automation securely unsubscribed users across all channels. Manual intervention and accidental resubscriptions disappeared.

• Efficiency: The operations team saved hours of manual work and minimized the chance of error.

• Scalability: The same design now works for WhatsApp, email, and push. Moreover, it only requires minor payload adjustments.

• Flexibility: The design can also automate subscriptions (opt-ins) or update user attributes whenever specific events occur.

🔮 Lessons for Next Time

Looking back, we see several improvements we could add:

• Automating CSV ingestion so blocked user lists upload on a schedule.

• Creating monitoring and alerts to flag users who might get mistakenly resubscribed.

• Integrating event triggers so unsubscribes happen in real time when conditions arise (for example, fraud detection or churn signals).

🤝 From Pain Point to Playbook

Manual unsubscribes were risky and time-consuming. Automating them with Braze APIs brought consistency, security, and peace of mind.

Have you faced similar challenges with communication blocking? Or do you use another way to manage multi-channel unsubscribes? Let’s exchange ideas — we’d love to hear from you.