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Email import is the process of uploading email addresses and contact data from external sources into an email marketing platform, CRM, or verification service. This typically involves uploading CSV or Excel files containing subscriber information, mapping data fields to the destination system, and processing the contacts for use in marketing campaigns or verification workflows.
Migrate contacts when switching email service providers
Upload purchased or acquired business contact lists for verification
Import leads collected from trade shows, webinars, or events
Consolidate subscriber lists from multiple sources into one platform
Bulk upload customers from an e-commerce platform for email marketing
Import contacts from CRM systems for targeted campaigns
Upload historical email data for re-engagement campaigns
Verify large contact databases before major email campaigns
Email import enables you to consolidate contacts from multiple sources into a single marketing platform or verify existing lists before sending campaigns. Without proper import capabilities, you would need to manually add contacts one by one, which is impractical for lists of any significant size. Efficient import processes also help maintain data integrity by detecting formatting issues, duplicates, and invalid entries during the upload process.
Email import begins by exporting your contacts from the source system as a CSV or Excel file. You then upload this file to your destination platform, which analyzes the columns and prompts you to map fields like email address, first name, and company to the corresponding fields in the system. The platform validates the file format, checks for duplicates against existing contacts, and processes the import. Most systems provide a summary showing successful imports, duplicates skipped, and any errors encountered.
Always verify imported email addresses before sending campaigns
Clean and format your CSV file before importing to reduce errors
Map fields correctly to preserve important subscriber data
Remove obvious duplicates and invalid entries before uploading
Start with a small test import to verify mapping is correct
Document the source and date of imported contacts for compliance
Segment imported contacts separately until you verify their quality
Check import results and address any errors or warnings
Most email platforms support CSV (Comma Separated Values) and Excel formats (XLS, XLSX). CSV is the most universal format and works across all platforms. Some services also support TXT files with tab or semicolon separators, or direct imports from other platforms via API integrations.
Ideally verify emails before importing to your email marketing platform. This prevents invalid addresses from entering your system and potentially hurting your sender reputation. Many verification services let you upload and verify lists, then download only the valid emails for import.
Most platforms offer options to skip duplicates, update existing records, or create duplicates. The best practice is to skip or update duplicates to maintain a clean list. Before importing, you can also use Excel or spreadsheet tools to identify and remove duplicates from your source file.
Check the error report provided by your platform to identify specific issues. Common problems include incorrect file encoding, missing required fields, or formatting errors in email addresses. Fix the issues in your source file, ensure proper UTF-8 encoding, and try importing again with a smaller batch first.
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