> ## Documentation Index
> Fetch the complete documentation index at: https://docs.struct.to/llms.txt
> Use this file to discover all available pages before exploring further.

# Event Volume Milestone

> Fire a webhook when an event's aggregated volume crosses a USD milestone.

<Note>
  **Event:** `event_volume_milestone` \
  **Cost:** 0.2 credits per delivery
</Note>

Fires when an event's aggregated cumulative volume crosses one of your USD milestones. The full payload schema is in the auto-generated [Event Volume Milestone callback](/api-reference/webhook-callbacks/event-volume-milestone-callback) reference; this page documents the filters and matching behavior.

## When to use this

* Track when an entire event reaches a notable volume threshold across all its markets.
* Spot trending events by watching aggregated volume cross $100K or $1M.
* Trigger alerts or workflows when an event hits a liquidity milestone within a chosen window.

## Subscription filters

Add these to the `filters` object when you create the subscription. `timeframes` is required.

| Filter                      | Type       | Description                                                                         |
| --------------------------- | ---------- | ----------------------------------------------------------------------------------- |
| `event_slugs`               | string\[]  | Restrict to specific events by slug (max 500).                                      |
| `timeframes`                | string\[]  | One or more windows: `1m`, `5m`, `30m`, `1h`, `6h`, `24h`, `7d`, `30d`, `lifetime`. |
| `milestone_amounts`         | integer\[] | USD milestone thresholds to fire on (max 500).                                      |
| `exclude_shortterm_markets` | boolean    | Exclude short-term Up/Down markets.                                                 |

## Example

```json theme={null}
{
  "url": "https://your-server.com/webhooks",
  "event": "event_volume_milestone",
  "filters": {
    "timeframes": ["24h"],
    "milestone_amounts": [100000, 1000000],
    "exclude_shortterm_markets": true
  }
}
```

## Notes

* `milestone_amounts` are USD thresholds. Each amount fires once when the aggregated cumulative volume crosses it.