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

# Pre-paid credits and usage-based billing

> How pre-paid credits and usage-based billing work in Quo, formerly OpenPhone.

Pre-paid credits let you pay in advance for usage-based services like international calling, texting, and automations. This makes it easy to manage variable usage without affecting your regular subscription billing.

## What credits cover

* **International calling**: Per-minute rates vary by country
* **International texting**: Per-message rates vary by country
* **API messaging**: \$0.01 per message plus standard rates
* **Zapier automation**: \$0.01 per message plus standard rates

## Messaging sent through the API or integrations

US and Canadian texts you send from the Quo app are included in your subscription at no extra cost. Messages sent through the **Quo API** or an **Integration** (such as Make, Zapier, or Clay) are billed differently.

These messages draw from your pre-paid **Voice & messaging balance** at **\$0.01 per segment** for US and Canada, plus standard rates for international destinations. They are not included in your subscription.

| Where the message is sent from          | How it's billed                                |
| --------------------------------------- | ---------------------------------------------- |
| Quo app (US/CA texts)                   | Included in your subscription                  |
| API or Integration (Make, Zapier, Clay) | \$0.01 per US/CA segment from pre-paid credits |
| International (any source)              | Per-segment rate varies by destination         |

<Note>
  If your pre-paid balance runs out, API and integration messages will fail, often with a "not enough prepaid credits" error, even though the same US/CA texts are free when sent from the Quo app. **Add funds or enable auto-recharge to avoid interruptions.**
</Note>

## How credits work

* **Per-usage deduction**: Credits consumed as you use services
* **Variable rates**: Each country has different calling/texting rates
* **Automatic billing**: Credits deducted from your balance automatically

***

## How to purchase pre-paid credits

1. Navigate to **Settings → Plan & billing**
2. Scroll to the **Voice & messaging balance**
3. Click **Add funds** to purchase

## Apply unused credits to your subscription

Have unused credits? Apply them to your subscription:

1. Navigate to **Settings → Plan & billing**
2. Scroll to the **Voice & messaging balance**
3. Click **Use towards subscription**
4. Confirm application

<Note>
  All credits are applied at once—you cannot specify a partial amount.
</Note>