User Import

There are two approaches for importing customer data into your Braze dashboard:


Braze’s User/Track REST API endpoint can be used to record custom events, user attributes, and purchases for users. See Braze’s User Track Endpoint documentation for more information.


Braze’s User Import feature allows users to upload and update user profiles via CSV files. This feature supports recording and updating user attributes such as first name and email, in addition to custom attributes such as shoe size.

When importing your customer data it is necessary to specify each customer’s unique identifier, also known as external_id. Before starting your CSV import it’s important to understand from your engineering team how users will be identified in Braze. Typically this would be a database ID used internally. This should align with how users will be identified by the Braze SDK on mobile and web, and ensures that each customer will have a single user profile within Braze across their devices. Read more about Braze’s user profile lifecycle.

When you provide an external_id, Braze will update any existing user with the same external_id or create a newly identified user with that external_id set if one is not found.

Download a CSV Import Template here.

Constructing Your CSV

Braze has several data types in Braze. When importing or updating user profiles via CSV, you can create or update Standard User Attributes or Custom Attributes.

Standard User Attributes are reserved keys in Braze, for example: first_name or email.

Custom Attributes are custom to your business: for example, a travel booking app may have a custom attribute called last_destination_searched.

When importing customer data, it is important that the Column Headers you use map exactly to the Standard User Attributes. Otherwise, Braze will automatically create a Custom Attribute on that user’s profile.

Braze accepts user data in the standard CSV format from files up to 100MB in size.

Download a CSV Import Template here.

Data Point Considerations

Each piece of customer data imported via CSV will overwrite the existing value on user profiles and will count as a data point*. Blank values will not overwrite existing values on the user profile, and you do not need to include all existing user attributes in your CSV file.

* External IDs uploaded via CSV will not consume data points. If you are uploading a CSV to segment existing Braze users by uploading ONLY external IDs, this can be done without consuming data points. If you were to add additional data like user email or phone number in your import, that would overwrite existing user data, consuming your data points.

Standard User Data Column Headers

external_id String A unique user identifier for your customer. Yes, see the following note
first_name String The first name of your users as they have indicated (e.g. Jane). No
last_name String The last name of your users as they have indicated (e.g. Doe). No
email String The email of your users as they have indicated (e.g. No
country String Country codes must be passed to Braze in the ISO-3166-1 alpha-2 standard (e.g. GB). No
dob String Must be passed in the format “YYYY-MM-DD” (e.g. 1980-12-21). This will import your user’s Date of Birth and enable you to target users whose birthday is “today”. No
gender String “M”, “F”, “O” (other), “N” (not applicable), “P” (prefer not to say), or nil (unknown). No
home_city String The home city of your users as they have indicated (e.g. London). No
language String Language must be passed to Braze in the ISO-639-1 standard (e.g. en).
List of accepted Languages
phone String A telephone number as indicated by your users (e.g. 541 754 3010). No
email_subscribe String Available values are opted_in (explicitly registered to receive email messages), unsubscribed (explicitly opted out of email messages), and subscribed (neither opted in nor out). No
push_subscribe String Available values are opted_in (explicitly registered to receive push messages), unsubscribed (explicitly opted out of push messages), and subscribed (neither opted in nor out). No
time_zone String Time zone must be passed to Braze in the same format as the IANA Time Zone Database (e.g. America/New_York or Eastern Time (US & Canada)). No

String May be passed in one of the following ISO8601 formats:
- “YYYY-MM-DDTHH:MM:SS” (e.g. 2019-11-20T18:38:57)
image_url String A URL of an image. No

Importing Custom Data via CSV

Any headers which do not exactly match nonstandard User Data will create a Custom Attribute within Braze.

These data types are accepted in User Import:

  • Datetime (Must be stored in the ISO 8601 format)
  • Boolean (TRUE/FALSE)
  • Number (Integer or Float with no spaces or commas, floats must use ‘.’ as the decimal separator)
  • String (no commas)
  • Blank (Blank values will not overwrite existing values on the user profile, and you do not need to include all existing user attributes in your CSV file.)

Importing a CSV

To import your CSV file, navigate to the User Import page under the Users section on the left-hand toolbar. In the lower text box, “Recent Imports”, there will be a table that lists up to twenty of your most recent imports, their file names, number of lines in the file, number of lines successfully imported, total lines in each file, and the status of each import.

Download a CSV Import Template here.

The upper box, “Import CSV”, will contain importing directions and a button to begin your import. Press the “Select CSV File” button and select your file of interest, then press “Start Upload.” Braze will upload your file and check the column headers as well as the data types of each column.

CSV Import

Once the upload is complete, you will see a modal window with a table previewing the contents of your file. All the information in this table is based on the values in the top few rows of your CSV file. For column headers, default attributes will be written in normal text, while custom attributes will be italicized and have their type noted in parentheses. There will also be a short summary of your file at the top of the pop-up.

You can import more than one CSV at the same time. CSV imports will run concurrently, and as such the order of updates is not guaranteed to be serial. If you require CSV imports to run in a serial fashion, you should wait until a CSV import has finished before uploading a second one.

If Braze notices something malformed in your file during the upload, errors will be shown above the summary. A file can be imported with errors, but once started, an import cannot be canceled or rolled-back. Review the preview, and if errors are found cancel the import and modify your file. It is important to examine the full file before upload as well. Braze does not scan every row of the input file at this stage; errors can exist which Braze does not catch while generating this preview.

Malformed rows and rows lacking an external ID will not be imported, all other errors can be imported, but may interfere with filtering when creating a segment.

CSV Import Errors

When you are satisfied with the upload, start the import. The pop-up will close and the import will begin in the background. You can track its progress on the User Import page, which will refresh every 5 seconds, or at the press of the refresh button in the Recent Imports box.

Under Lines Processed, you will see the progress of the import; the status will change to Complete when finished. You can continue to navigate around other parts of Braze during the import, you will receive modal notifications when the import begins and ends.

When the import process runs into an error, a yellow warning icon will be displayed next to the total number of lines in the file. You can mouse over the icon to see details into why certain lines failed. Once the import is complete, all data will have been added to existing profiles or all-new profiles will have been created.


User Import creates and updates user profiles, and can also be used to create segments. To create a segment, check the ‘Create a segment from this CSV’ box.

CSV Import Segmenting Users

You can set the name of the segment or accept the default, which is the name of your file. Files that were used to create a segment will have a link to view the segment once the import has been completed.

The filter used to create the segment selects users who were created or updated in a selected import and is available with all other filters in the edit segment page.


Malformed Row

There must be a header row in order to properly import data. Each row must have the same number of cells as the header row. Rows whose length has more or fewer values than the header row will be excluded from the import. Commas in a value will be interpreted as a separator and can lead to this error being thrown. Additionally, all data must be UTF-8 encoded.

Multiple Data Types

Braze expects each value in a column to be of the same data type. Values that do not match their attribute’s data type will cause errors in segmenting.

Incorrectly Formatted Dates

Dates not in the ISO 8601 format will not be read as datetimes on import.

String Quotation

Values encapsulated in single (‘’) or double (“”) quotation marks will be read as strings on import.

Data Imported as Custom Attribute

If you are seeing a piece of Standard User Data (e.g. email or first_name imported as a Custom Attribute), check the case and spacing of your CSV file. First_name would be imported as a Custom Attribute, first_name would be correctly imported into the “first name” field on a user’s profile.

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