
Bulk import
Add thousands of contacts at once with a simple spreadsheet upload
Automatic deduplication
No need to worry about duplicates—Brew handles them automatically
Custom properties support
Include any custom fields you want to add or update with your contacts
Getting Started with CSV Uploads
1
Prepare your CSV file
Create a CSV file with the following columns:Required column:
Email
- The contact’s email address
First Name
- The contact’s first nameLast Name
- The contact’s last name
Subscribed
- Whether the contact is subscribed (usetrue
orfalse
, defaults totrue
if not specified)- Any custom properties you’ve created in Brew

Download our example CSV template to ensure your file is correctly formatted.
2
Access the import screen
- Go to the Audience page
- Click the Add Contacts button in the top right corner
- Select CSV Upload from the dropdown menu

3
Upload your CSV file
- Drag and drop your CSV file into the upload area or click to browse your files
- Wait for the file to upload and process

4
Map CSV columns to Brew properties
After uploading, you’ll see a column mapping screen:
- Ensure each CSV column is correctly mapped to the corresponding Brew property
- For any columns that don’t have a default mapping, select the appropriate property from the dropdown
- Click Continue when the mapping is complete

If your CSV contains columns for custom properties that don’t yet exist in Brew, they will be automatically created during the import process.
5
Review and confirm
Review the import summary, which shows:
- Total contacts to be added or updated
- Any potential issues or errors
- Option to trigger automations for new contacts
- Option to add contacts to subscription groups

6
Complete the import
Click Complete Import to finalize the process.You’ll see a success message when the import is complete, and your contacts will be available in your Audience.
Adding Contacts to Subscription Groups During Import
During the import process, you can optionally add the imported contacts to one or more subscription groups:1
Enable subscription group option
On the review screen, toggle on Add to subscription groups

2
Select subscription groups
Choose the subscription groups you want to add the contacts to from the dropdown menu
3
Complete the import
Continue with the import process as normal
This will only add contacts to the selected groups - it won’t remove them from any groups they might already belong to.
Updating Existing Contacts
You can also use CSV upload to update existing contacts:Matching existing contacts
Matching existing contacts
Brew identifies existing contacts using the email address:
- If an email in your CSV matches an existing contact, that contact will be updated
- If no match is found, a new contact will be created
Partial updates
Partial updates
When updating contacts, empty cells in your CSV will not overwrite existing data.If you want to clear a field, you must use the value
null
(4 characters, all lowercase) in the CSV cell.Subscription status
Subscription status
Important notes about the
Subscribed
column:- If not included, all new contacts will be marked as subscribed by default
- To import unsubscribed contacts, include a
Subscribed
column withfalse
values - The importer will not re-subscribe contacts who have previously unsubscribed
Triggering Automations for Imported Contacts
You can optionally trigger automations when importing contacts:1
Enable automation triggers
On the review screen, toggle on Trigger automations

2
Understand which automations will trigger
This will trigger:
- For new contacts: Automations with “Contact added” triggers
- For updated contacts: Automations with “Contact updated” triggers
- If adding to subscription groups: Automations with “Added to subscription group” triggers
3
Complete the import
Continue with the import process as normal
Be careful when enabling this option with large imports, as it could trigger a high volume of emails.
Viewing Import History
You can view a history of your past CSV imports:
- Go to the Audience page
- Click Add Contacts → CSV Upload
- Click View imports
- This shows all previous imports with details like:
- Import date and time
- Number of contacts imported
- Success/error rates
- Click on any import to see detailed information
Troubleshooting Common CSV Issues
Duplicate contacts
Duplicate contacts
If your CSV contains duplicate email addresses:
- Only the last row with that email will be imported
- You’ll see a warning in the review step showing the number of duplicates
Invalid email formats
Invalid email formats
Emails must be in a valid format (e.g., name@domain.com).Invalid emails will be flagged during the review step and will not be imported.
Encoding issues
Encoding issues
If your CSV contains special characters:
- Ensure your CSV is UTF-8 encoded
- If you see garbled text in the column mapping screen, try re-exporting your CSV with UTF-8 encoding
Large file handling
Large file handling
For very large CSV files:
- There’s a 10MB file size limit
- For files with 100,000+ contacts, the import may take several minutes
- Consider splitting very large files into smaller batches
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