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

# Phone Numbers

> Purchase and manage dedicated phone numbers for your applications

Phone numbers are required to send and receive SMS and MMS messages. Before you can start messaging, you need to purchase at least one phone number and assign it to your application.

## Phone Number Types

Chirp offers different types of phone numbers for different use cases:

<AccordionGroup>
  <Accordion title="Local Numbers">
    Standard phone numbers with a local area code. Best for:

    * Regional businesses and services
    * Lower per-message costs
    * Building local trust with customers
  </Accordion>

  <Accordion title="Toll-Free Numbers">
    Numbers with prefixes like 800, 888, 877, etc. Best for: - National campaigns and services -
    Customer support lines - Professional brand image
  </Accordion>

  <Accordion title="Short Codes (US only)">
    5-6 digit numbers for high-volume messaging. Best for: - Marketing campaigns - Two-factor
    authentication - Time-sensitive alerts - Higher throughput requirements
  </Accordion>

  <Accordion title="Alphanumeric Sender IDs (UK and select countries)">
    Custom text-based sender names instead of numbers. Best for:

    * Brand recognition
    * One-way messaging
    * Marketing communications
  </Accordion>
</AccordionGroup>

<Note>
  Number type availability varies by country. [View pricing](/getting_started/pricing) to see what's
  available in your region.
</Note>

## Pricing

Phone numbers have two cost components:

1. **Purchase fee** - One-time cost to acquire the number
2. **Monthly rental fee** - Recurring cost to maintain the number

See the [pricing](/getting_started/pricing) page for detailed rates.

## Assigning Numbers to Applications

Phone numbers must be assigned to an [application](/concepts/applications) before they can send or receive messages. You can assign the same phone number to multiple applications, allowing you to reuse numbers across different projects.

Each application uses its own API keys and webhook configuration, so the same number can behave differently depending on which application is handling the message.

See [Managing Phone Numbers](/sms/managing-numbers) for more information on how to assign phone numbers to your application.