# au

> au is Japan's second-largest mobile carrier, with approximately 27% market share.

 au is Japan's second-largest mobile carrier, with approximately 27% market share. As one of the three major carriers in Japan (alongside NTT Docomo and [SoftBank](https://docs.antom.com/ac/antomop/softbank.md)), au offers reliable carrier billing services to its customers.

## Properties {#djNTu}

 The following table lists the product properties supported by au:

 | **Payment type** | Carrier billing |  |  |
| --- | --- | --- | --- |
| **Acquirer** | AntomSG, AntomHK, AntomUS, AntomUK, AntomEU, AntomJP | **Merchant entity location** | SG, HK, US, UK, EEA, JP |
| **Payment flow** | Redirect | **Refund** | ✔️ |
| **Buyer country/region** | Japan | **Partial refund** | ❌ |
| **Processing currency** | JPY | **Chargeback/Dispute** | ❌ |
| **Minimum payment amount** | 1 JPY | **Refund period** | 60 days |
| **Maximum payment amount** | 500,000 JPY | **Time to return payment result** | Real-time |
| **Default timeout** | 14 minutes |  |  |

## User experience {#3fda4231}

 > **[INFO]** **Note**   : The following payment flows on different terminals are reference only, and represent this payment method's flow on different terminal types. For supported merchants' terminal types, consult Antom Technical Support.

 The following figures show the journey of paying with au:

<!-- TabGroup -->

**Tab: Web**

![image.png](https://intranetproxy.alipay.com/skylark/lark/0/2026/png/122457175/1776848436790-2695578e-7ff5-46a5-92d3-71fe242dcb91.png)

 1. The buyer selects au to pay.
2. The buyer is redirected to the au page and logs in with the au ID.
3. The buyer completes the verification by entering a 6-digit code sent to the phone.
4. The buyer confirms the payment details and enters the payment 4-digit PIN of the au account to complete the payment.
5. The buyer is redirected back to the merchant result page.

**Tab: WAP**

![image.png](https://intranetproxy.alipay.com/skylark/lark/0/2026/png/122457175/1776848449571-27396b5f-63d0-44a3-98f7-7b871ec896b0.png)

 1. The buyer selects au to pay.
2. The buyer is redirected to the au page and logs in with the au ID.
3. The buyer completes two-factor verification by entering a 6-digit code sent to the phone.
4. The buyer confirms the payment details and enter the payment 4-digit PIN of the au account to complete the payment.
5. The buyer is redirected back to the merchant result page.

<!-- /TabGroup -->

## Supported online payment integrations {#ZdPPk}

 Antom offers a range of integration options tailored to each payment method. Each payment method may support different online payment integration options, allowing for flexibility based on your business requirements. The table below provides detailed information about the specific integrations available for each payment method:

 | **Supported online payments** | **Supported integrations** |
| --- | --- |
| One-time Payments | ✔️      [API-only](https://docs.antom.com/ac/cashierpay/apm_api.md) ❌    Hosted Checkout Page ❌    Embedded Checkout Page ❌    Web Element ❌    Mobile Element ❌    Payment links |
| Tokenized Payment | ❌ |
| Subscription Payment | ❌ |
| EasySafePay | ❌ |
| Scan to Link | ❌ |