> ## 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.

# Does the Hologram SIM support voice calling?

> Hologram IoT SIMs support VoIP communications using data.

Hologram's SIMs are designed for the Internet of Things (IoT) and Machine to Machine (M2M) communications. They only support data usage and SMS messaging. However, data can be used for VoIP communications.

<Note>
  **Note:** VoIP communications will consume data according to your device's codec and call duration.
</Note>

## Related actions

<Card title="Send messages to SIMs" icon="message" href="/dashboard/sim-actions/send-messages-to-sims" horizontal>
  Send SMS, TCP, or UDP messages to your devices
</Card>

<Card title="SIM pricing" icon="dollar-sign" href="/dashboard/sims/sim-details-pricing-tab" horizontal>
  Review pricing information for your SIMs
</Card>