> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.zip.tax/v-5-0/guides/webhooks/overview/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.zip.tax/_mcp/server. # Event Webhooks Overview Event Webhooks let your account receive real-time HTTP notifications when something changes in Ziptax, instead of polling the API. When a subscribed event occurs, Ziptax sends an HTTP `POST` request with a JSON body to each endpoint URL your account has configured. > **Warning** > > The webhook body is only a notification that something changed. It does not > carry the changes themselves. For `rate.updated`, the payload tells you which > tax authority changed (and, at [Postal code granularity](configure#granularity-level) > on Enterprise plans, which postal codes were affected). When you receive it, > call the [Ziptax rate API](../rest-api/overview) to fetch the updated rates for > that authority. ## How it works ### You configure one or more endpoints Add the HTTPS URLs that should receive notifications from your account's `Develop > Events` page. ### A subscribed event occurs For example, sales tax rates change for a tax authority you care about. ### Ziptax delivers the event Ziptax sends an HTTP `POST` with a JSON body to **every** configured endpoint. ### Your endpoint acknowledges, then acts Respond quickly with a `2xx` status, then fetch the authoritative data from the Ziptax API. ## When to use webhooks Use Event Webhooks when you want to react to changes as they happen without running a polling loop against the API. The current use case is keeping your own cached rates fresh: subscribe to `rate.updated` and re-fetch rates for an authority only when it actually changes. ## Explore the docs #### [Prerequisites & access](prerequisites) Plan requirements, roles, and where to find the feature. #### [Configure an endpoint](configure) Add endpoint URLs and choose which events to subscribe to. #### [Events reference](events) The event catalog and payload schema. #### [Verify & secure deliveries](verify) The signing secret and how to keep endpoints secure. #### [Test & monitor](testing) Send test events and check delivery status. #### [Best practices](best-practices) Patterns for reliable, secure webhook handling. > Get real-time HTTP notifications when data changes in Ziptax, instead of polling