# Register Viber contacts

For a customer to receive Viber messages, they must have a valid phone number and be registered as a Viber platform subscriber in Pushwoosh. This guide explains how to register contacts by importing a CSV file.

<Aside type="note" title="Automatic registration">
When a contact messages your Viber Business account for the first time, Pushwoosh registers their phone number as a Viber subscriber automatically.
</Aside>

## How to import Viber contacts from a CSV file

To import Viber contacts, upload a CSV file containing the contact list. The imported numbers will be registered as Viber subscribers, enabling personalized messaging and audience segmentation.

### Prepare your CSV file

#### CSV formatting rules

##### General structure
- The first row must contain column headers describing the data in each column.
- Each subsequent row represents a single contact, with values corresponding to the headers.
- Values must be separated by commas.
- Save the file in UTF-8 encoding to ensure proper character display.
- The maximum allowable file size is 100 MB.

##### Required columns
- **Phone Number:** Must be in [**E.164**](https://en.wikipedia.org/wiki/e.164) format, including the `+` sign and country code.
- **User ID:** A unique identifier for the user (e.g., name or email).

<Aside type="note">
The column names in your CSV file don't need to match these exactly. During the import process, you can map your existing column names to the correct fields in the system. For example, if your CSV file has a column named *Mobile* instead of *Phone Number*, you can manually assign it to the **Phone Number** field when importing.
</Aside>

##### Optional columns
Adding optional columns allows for more advanced segmentation and personalization in your Viber campaigns.

- **Name:** First name or full name of the user.
- **Location:** Specifies the user's city, state, or country. Useful for sending location-based promotions (e.g., *Get 20% off at our Los Angeles store today!*).
- **Birthday:** Enables sending birthday messages with special discounts (e.g., *Happy Birthday, Sarah! Here's a 10% discount just for you!*). Can trigger automated birthday campaigns.
- **Language:** Stores the user's language preference (e.g., English, Spanish, French). Helps send messages in the recipient's language for better engagement.
- **Customer Type:** Identifies whether the user is a **new customer, VIP, or inactive**. Enables targeted messaging (e.g., *Exclusive VIP offer just for you!*).
- **Custom Tags:** Any additional data relevant to your campaign (e.g., user preferences, purchase history). These can be mapped to system tags and used for segmentation in Pushwoosh.

##### Example CSV file

The following example shows a properly formatted CSV file:

```csv
Phone Number,User ID,Name,Location
+1XXXXXXXXXX,john.doe@email.com,John Doe,New York
+1XXXXXXXXXX,jane.smith@email.com,Jane Smith,Los Angeles
```

### Upload the CSV file

1. Go to **Audience > Import CSV > Import Viber Contacts**.

<img src="/viber-register-viber-contacts-1.webp" alt="Import CSV menu in Audience section showing Import Viber Contacts option for uploading Viber subscriber phone numbers"/>

2. Select your CSV file from your computer.

3. Map columns:

   * **Viber Contact Column in CSV:** Choose the column containing phone numbers in E.164 format (e.g., `+1XXXXXXXXXX`). Pushwoosh registers them internally as `viber:+` subscribers.
   * **User ID Column in CSV:** Select the column with unique user identifiers (e.g., email or name).

<img src="/viber-register-viber-contacts-2.webp" alt="Import Viber contacts Map step with Viber contact column and User ID column dropdowns for CSV mapping"/>

4. Add additional data (optional)

   If you want to include extra details for segmentation:

   * Select a **Column Name** from your CSV.
   * Assign it a **Tag** to link it with user data in the system.
   * Click **+ Add Column** to include more attributes.

<img src="/viber-register-viber-contacts-3.webp" alt="Viber CSV import optional tag mapping with Column Name and Tag dropdowns and Add Column link"/>

5. Click **Start Import** to begin processing the file.

Once the CSV import is complete, the contacts will appear as a new segment in the [Segments list](/product/audience-data-and-segmentation/segmentation/) and will also be available in [User explorer](/product/audience-data-and-segmentation/user-explorer/).

You can then use this data to create segmented and personalized Viber campaigns via Customer Journey.

<LinkCard title="Learn more about sending Viber messages" href="/product/messaging-channels/viber/send-viber-messages/" />