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Creating Import Files for Your Contacts

Last Updated: Sep 30, 2025

Learn how to properly format your contact files for a smooth import into Sender.

Supported File Formats

Sender accepts the following file types:

  • CSV (.csv)
  • TXT (.txt)
  • MS Excel (.xlsx)

Maximum file size: 64MB

File Structure Requirements

Column Headers (First Row)

Your file must include headers in the first row to identify each field:

  • Email address (required)
  • First name (optional)
  • Last name (optional)
  • Custom fields (optional)

Data Rows

  • Each subscriber must be on a separate row
  • All subscriber information should be in separate columns
  • No empty rows between contacts

File Example

Download Templates

Not sure how to format your file? Download our ready-to-use templates:

  • Excel template – For .xlsx files
  • CSV template – For .csv files

Simply fill in your contact information following the template structure.

Tips for Success

  • Ensure email addresses are valid and properly formatted
  • Remove any duplicate entries before importing (Our system does catch duplicates whether you remove them or not, but this helps the import itself)
  • Double-check that all data is in the correct columns
  • Save your file in one of the supported formats

That’s it!

If you got stuck on a specific task or can’t find a way to execute a particular job, contact our support team via LiveChat or [email protected] – we’re here to help 24/7.

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