---
title: "Estimate the credit runway"
description: "Days until the credit balance runs out at the last 7 days' rate of spend: floor(balance ÷ (spend in the last 7 days ÷ 7))."
canonical_url: "https://twominutebilling.com/help/developers/api-reference/usage-controls/estimate-the-credit-runway"
---
# Estimate the credit runway

> Days until the credit balance runs out at the last 7 days' rate of spend: floor(balance ÷ (spend in the last 7 days ÷ 7)).

<api-operation method="GET" path="/v1/businesses/{biz}/customers/{cus}/credit_runway">
<template v-slot:docs="">

Counts what an active automatic top-up can still add this month. `runway_days` is null with under 24 hours of usage or no spend. An estimate.

## Path parameters

<table>
<thead>
  <tr>
    <th>
      Parameter
    </th>
    
    <th>
      Type
    </th>
    
    <th>
      Required
    </th>
    
    <th>
      Description
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      <code>
        biz
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      <strong>
        yes
      </strong>
    </td>
    
    <td>
      The business's id (biz_…).
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        cus
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      <strong>
        yes
      </strong>
    </td>
    
    <td>
      The customer's id (cus_…).
    </td>
  </tr>
</tbody>
</table>

## Query parameters

<table>
<thead>
  <tr>
    <th>
      Parameter
    </th>
    
    <th>
      Type
    </th>
    
    <th>
      Required
    </th>
    
    <th>
      Description
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      <code>
        currency
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      no
    </td>
    
    <td>
      The balance currency. Default: the customer's.
    </td>
  </tr>
</tbody>
</table>

## Response

<table>
<thead>
  <tr>
    <th>
      Field
    </th>
    
    <th>
      Type
    </th>
    
    <th>
      Description
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      <code>
        object
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      The object type; always <code>
        credit_runway
      </code>
      
      . One of <code>
        credit_runway
      </code>
      
      .
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        customer
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      cus_…
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        currency
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      ISO 4217.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        estimate
      </code>
    </td>
    
    <td>
      <code>
        boolean
      </code>
    </td>
    
    <td>
      The credit runway's estimate. One of <code>
        true
      </code>
      
      .
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        runway_days
      </code>
    </td>
    
    <td>
      <code>
        integer
      </code>
    </td>
    
    <td>
      Whole days. Null: not enough usage to estimate.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        runs_out_at
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      ISO 8601.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        balance_minor
      </code>
    </td>
    
    <td>
      <code>
        integer
      </code>
    </td>
    
    <td>
      Live credit balance.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        burn_minor_per_day
      </code>
    </td>
    
    <td>
      <code>
        integer
      </code>
    </td>
    
    <td>
      Spend in the last 7 days ÷ 7.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        spend_last_7_days_minor
      </code>
    </td>
    
    <td>
      <code>
        integer
      </code>
    </td>
    
    <td>
      Rated usage in the last 7 days.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        auto_topup_minor
      </code>
    </td>
    
    <td>
      <code>
        integer
      </code>
    </td>
    
    <td>
      What an active automatic top-up can still add this month.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        message
      </code>
    </td>
    
    <td>
      <code>
        string
      </code>
    </td>
    
    <td>
      The estimate in words.
    </td>
  </tr>
</tbody>
</table>

## Status codes

<table>
<thead>
  <tr>
    <th>
      Status
    </th>
    
    <th>
      Meaning
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      <code>
        200
      </code>
    </td>
    
    <td>
      The runway estimate.
    </td>
  </tr>
  
  <tr>
    <td>
      <code>
        404
      </code>
    </td>
    
    <td>
      No such customer.
    </td>
  </tr>
</tbody>
</table>
</template>

<template v-slot:request="">

```bash [Request]
curl "$TMBILLING_URL/v1/businesses/biz_XXXXXXXXXXXX01/customers/cus_XXXXXXXXXXXX01/credit_runway" \
  -H "Authorization: Bearer $TMBILLING_API_KEY"
```

</template>

<template v-slot:response="">
<code-group>

```json [200 OK]
{
  "object": "credit_runway",
  "customer": "cus_XXXXXXXXXXXX01",
  "currency": "USD",
  "estimate": true,
  "runway_days": 14,
  "runs_out_at": "2026-03-14T09:30:00Z",
  "balance_minor": 2900,
  "burn_minor_per_day": 14,
  "spend_last_7_days_minor": 2900,
  "auto_topup_minor": 2900,
  "message": "Requested by the customer."
}
```

```json [404 Not Found]
{
  "error": {
    "type": "invalid_request_error",
    "message": "No such customer."
  }
}
```

</code-group>
</template>
</api-operation>


## Sitemap

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