Import Phone Numbers

How to add Phone Numbers to use OneSignal SMS feature

This guide explains how to upload a CSV list of phone numbers through the dashboard or manually add phone numbers if needed. Other options include:


Duplicate Phone Number Records

OneSignal will automatically remove duplicate sms subscriptions. If the sms subscription is marked as unsubscribed, it will continue to be marked unsubscribed unless updated.

Dashboard CSV Upload


  • Must have phone_number column with lower-case spelling. (All property headers need to have the same case as indicated on the import page. e.g., must use "phone_number" and not "Phone_Number")
  • Limited to UTF-8 encoding.
  • Columns must be unique.
  • No quotes.
  • Commas only, no semi-colons.
  • No Data Tags.
  • Remove any + sign from your CSV file name.


Data Tag Uploads

It is recommended to upload your sms and/or email subscriptions with the external_id first. Then use the Update data tags CSV.

CSV Column Options

These are the available properties you can set in the first row of your CSV.

Column HeadersDescription
phone_numberRequired The phone number to be imported. Must be in the E.164 format
external_idRequired The user ID for identifying the owner of the phone number. See Aliases & External ID for details.
subscribedWhether the phone number is opted-in to receive sms. Values can be yes or no. If column is not present, all phone numbers default to being opted-in (yes).
countryThe ISO 3166-2 country code of the user. 2 characters, all caps.
timezone_idThe timezone of the user in IANA TZ format.
languageThe language code of the user in ISO 639-1 format

Example CSV Column Headers:


CSV Upload Steps

Navigate to Audience > Subscriptions > Update/Import Users.

Under "Import/Update phone_numbers" select Upload CSV. There is also an Example CSV template you can download to check your format.

After uploading check for any errors. You may need to fix the CSV then upload again if you have any errors.

Advanced Settings

If you want to create a segment to send messages to this list, toggle on the Automatically create a segment for this import to set a new tag and create a segment for these users.

Manually Add Phone Numbers

Navigate to Audience > Subscriptions > Arrow next to Update/Import Users > Manually Add Phone Numbers to open a new modal where you can add an individual user's phone number.



Once you've imported your phone numbers, go back to SMS Quickstart to determine if you have any steps left.

What’s Next