How do I manage and add more addresses to a Webhook?

Last updated: August 25, 2026

Alchemy’s webhooks allow you to monitor blockchain events for up to 100,000 addresses. Managing these addresses, including adding or removing them, can be done through the update-webhook-addresses endpoint. Below, we’ll guide you through the process of updating addresses across any webhook, and how to handle large address lists efficiently.

Managing Addresses with update-webhook-addresses

The update-webhook-addresses endpoint can be used to add or remove addresses tracked by any webhook. However, there are important limitations to note:

  • Maximum Addresses per Webhook: Each webhook can track up to 100,000 addresses.

  • Request Limit: The update-webhook-addresses endpoint accepts an array with a maximum of 500 addresses per request to ensure system safety and performance.

How to Add More Than 500 Addresses?

If you need to add more than 500 addresses to a webhook, follow these steps:

  1. Divide the Address List: Split your large address array into smaller arrays, each containing a maximum of 500 addresses.

  2. Make Multiple API Calls: Call the update-webhook-addresses endpoint multiple times, passing one array of 500 addresses per request. This ensures that you can add as many addresses as necessary.

  3. API Reference: For more detailed instructions on how to structure your API requests, refer to our API documentation.

Example:

If you want to track 1,000 addresses with your webhook, you would:

  1. Split the 1,000 addresses into 10 arrays of 500 addresses each.

  2. Call the update-webhook-addresses endpoint 10 times, with one array per call.

  3. Repeat this process until all the addresses are successfully added to the webhook.

Rate Limits for Webhook Management Endpoints

Requests to Alchemy's webhook management endpoints (the Notify API) are capped by requests per minute, separate from your account's Throughput Limit (CUPS):

  • create-webhook, team-webhooks, test-webhook: 300 requests/min (5 requests/sec)

  • update-webhook, delete-webhook, update-webhook-addresses: 600 requests/min (10 requests/sec)

If you hit a 429 on these endpoints, it's this per-endpoint limit, not your account's CU-based Throughput Limit. Webhook event delivery itself doesn't count against either limit. When bulk-updating addresses, spacing out your batched calls (or adding retry with backoff on a 429) will keep you under the limit.

Best Practices

  • Batching Requests: To prevent overloading the system and hitting rate limits, it’s recommended to add addresses in batches, as outlined above.

  • Tracking Limit: While each webhook can track up to 100,000 addresses, you can always create additional webhooks if you need to monitor more addresses.

By following these steps, you can effectively manage and add addresses to any of your webhooks, ensuring a scalable and reliable system!