---
updatedAt: 2025-11-06T18:06:47.000Z
agentTools:
  projectIndex: https://developer.marchex.io/llms.txt
---

# Number Assignment from Inventory

When creating a Tracking Number, you can choose to assign a number found using our **[Local Numbers](https://developer.marchex.io/docs/finding-local-numbers)** or **[Toll-Free](https://developer.marchex.io/docs/finding-toll-free-numbers)** search API.

When creating a number, the following values must be passed:

* name - a unique name to identify the number for reporting purposes
* phone\_number - the number that was retrieved via the AvailableNumbers resource
* route\_type - how the call should be routed to the Advertiser (see the **[Create Number](https://developer.marchex.io/reference/post_api-groups-groupid-numbers)** section the API Reference for additional information).  Basic routing is being used in this example
* termination\_number - a 10 digit phone number where calls should be forwarded to

To create a tracking number using this method, submit the following POST request to the Number resource:

```json Request
{
    "name": "ABC company",
    "phone_number": "4043411118",
    "call_routes": {
        "route_type": "Basic",
        "termination_number": "4045551234"
    }
}
```

A successful post will result in the creation of a tracking number:

```json Response
{
    "id":938472,
    "name": "ABC company",
    "phone_number": "4043411118",
    "call_routes": {
        "route_type": "Basic",
        "termination_number": "4045551234"
    }
}
```