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

# Monitor usage with data usage warning thresholds

> Data warnings help you monitor data usage and take action before incurring additional charges or reaching a data usage limit. Set a data warning threshold to create an [event](/guides/cloud-and-tools/event-types-and-tags) when a certain amount of data is reached. Then, create an [alert](/dashboard/event-monitoring/alerts-and-notifications) to be notified when the threshold is reached.

## What are data usage warning thresholds?

Data warning thresholds are set per-SIM, and are triggered when a SIM's usage crosses a threshold you define after a data session closes. Data warning thresholds, like data usage limits, are tracked at the SIM's unique 30-day billing cycle. **Data usage thresholds do not prevent data usage**, they create events that you can monitor with alerts to then take action before incurring additional charges or reaching a data usage limit.

For automated data usage enforcement, combine data usage warnings with [data usage limits](/dashboard/sim-actions/set-usage-limits) to track usage, and then manage data usage before the limit is reached and your SIM is paused.

<Warning>
  **Warning:** Data usage thresholds do not pause SIM data. To automatically stop data at a threshold, set a **[data usage limit](/dashboard/sim-actions/set-usage-limits)** instead.
</Warning>

This value is the `datathreshold` parameter returned in the REST API.

## Set a data warning threshold for a single SIM

1. Find the SIM in the SIMs pages or using global search.
2. Open the **Manage SIM** menu in the header, and select **Set data warning threshold**.
3. Enter the threshold amount in KB/MB/GB, and confirm the update.

## Set data warning thresholds in bulk

You can apply usage thresholds for up to 10,000 SIMs at a time from the SIMs pages.

1. Navigate to the **SIMs** section in your dashboard and open the **Active SIMs** page.
2. Use filters and sorting to find and select the SIMs you want to set usage thresholds for.
3. Open the **Manage SIMs** menu at the top of the page and choose **Set data warning threshold**.
4. Configure the usage threshold settings and select **Update**.

<Warning>
  **Warning:** When updating data usage thresholds in bulk, all existing thresholds will be replaced.
</Warning>

## Set data warning thresholds during activation or when changing data plans

In the **Review rates and coverage** step of the SIM activation and change data plan process, you can set a new data usage threshold for your selected SIMs.

<Danger>
  **Warning:** When updating data usage thresholds during activation or when changing data plans, all existing thresholds will be removed. If you specify a new usage threshold for your SIMs, all existing thresholds will be replaced with the new setting.
</Danger>

## Set data warning thresholds using the REST API

<Card title="Set data warning thresholds (bulk)" href="/api/1/devices/batch/usagelimit/post">
  Set data warning thresholds (bulk) <code>POST /devices/batch/usagelimit</code> (use the `datathreshold` parameter)
</Card>

## Related actions

<Card title="Set data warning thresholds" href="/dashboard/sim-actions/set-usage-limits">
  Set a data usage limit for all selected SIMs to prevent unexpected data usage charges or overage.
</Card>

<Card title="Single SIM actions overview" href="/dashboard/sim-actions/single-sim-actions-overview">
  Take actions on a single SIM from its details page with full control over SIM management.
</Card>