Import Data from CSV/Excel
101 · Step 4
Migration Guide
Migrate contacts, companies, and deals from spreadsheets or other CRMs.
By Sebastian StreiffertPublished Jan 10, 2026Updated May 29, 20266 min read
Overview: Importing Data into Lumenbase
Use the import wizard to migrate your existing contacts, companies, deals, and invoices from spreadsheets or other CRM systems. Whether you move from Excel, Google Sheets, or another CRM, the wizard handles field mapping, duplicate detection, and data validation for you.
Supported Formats
Import from CSV (.csv) and Excel (.xlsx, .xls) files. Export from your current system in either format to get started.
Moving from a previous CRM with a full workspace copy? Use the migration wizard in Data Hub instead of CSV. See CRM workspace migration wizard.
Smart Field Mapping
The import wizard automatically suggests field mappings based on column headers, saving time and reducing errors during migration.
Duplicate Detection
Built-in duplicate detection identifies existing records that match your import data, with options to skip, merge, or create new records. Learn more aboutfinding and merging duplicates.
Supported Entity Types
You can import the following record types:
| Entity Type | Key Fields | Duplicate Matching |
|---|---|---|
| Contacts | Name, Email, Phone, Company, Title | Email or LinkedIn URL |
| Companies | Name, Website, Industry, Size | Company name (case-insensitive) |
| Deals | Name, Value, Stage, Company, Contact | Deal name + company |
| Invoices | Number, Amount, Company, Date | Invoice number |
Import companies before contacts if your contacts need to be linked to companies. Import contacts before deals if your deals reference contacts.
Preparing Your Data
Proper data preparation ensures a smooth import. Follow this checklist before uploading:
Data Preparation Checklist
- Include a header row with descriptive column names
- Remove duplicate rows from your source file
- Standardize date formats (YYYY-MM-DD works best)
- Clean up inconsistent data (e.g., 'USA' vs 'United States')
- Ensure email addresses are properly formatted
- Remove any formulas - save as values only
- Split full names into first/last name columns if possible
Recommended Column Headers
Use these header names for automatic field mapping:
| For Contacts | For Companies | For Deals |
|---|---|---|
| first_name, last_name | company_name | deal_name |
| website | value | |
| phone | industry | stage |
| title | company_size | close_date |
| company | address | contact |
| linkedin_url | phone | company |
Step-by-Step Import Guide
Follow these steps to import your data into Lumenbase:
1
Open the Data Hub
Go to
System Operations → Data Hub in the sidebar and stay on the Import tab.2
Pick a Starting Point
Smart import auto-detects the record type from your file. To be explicit, pick a card under By record type instead: Contacts, Companies, Deals, or Invoices. Either way, the choice determines which fields are available for mapping.
3
Upload Your File
Drag and drop your CSV or Excel file, or click to browse. The wizard previews your data and detects column headers automatically.
4
Map Fields
Match your file columns to Lumenbase fields:
- Required fields are marked with an asterisk (*)
- Auto-detected mappings appear pre-selected
- Click a column to change its mapping
- Unmapped columns will be skipped
- Map to custom fields if standard fields don't match
5
Configure Link Fields
For Contacts and Deals, configure how records link to other entities:
- Contacts: map a column to 'Company' to auto-link to existing companies
- Deals: map columns for linked company and primary contact
- The wizard matches by name, so make sure names match existing records exactly
6
Set Duplicate Strategy
Choose how to handle records that match existing data:
| Option | Behavior |
|---|---|
| Skip Duplicates | Existing records are left unchanged |
| Update Duplicates | Merge new data into existing records |
| Create All | Import all rows as new records (may create duplicates) |
7
Review and Import
Preview the first few rows with your mappings applied. If everything looks correct, click Start Import to begin.
Duplicate Detection
Lumenbase automatically detects potential duplicates during import based on key identifying fields:
Matching Rules by Entity
| Entity | Primary Match Field | Secondary Match |
|---|---|---|
| Contacts | Email address | LinkedIn URL |
| Companies | Company name (case-insensitive) | Website domain |
| Deals | Deal name + Company | - |
| Invoices | Invoice number | - |
Duplicate Resolution Options
When duplicates are detected, you can:
- Skip: Keep the existing record, don't import the duplicate row
- Update/Merge: Combine data from both records (new data fills empty fields)
- Create New: Import as a separate record despite the match
If you're not sure about duplicates, choose 'Skip Duplicates' for your first import. You can always do a second import with 'Update' to fill in missing data.
Handling Large Imports
Large imports (1,000+ records) are processed in the background using batch processing. Here's what to expect:
- Progress indicator shows completion percentage
- You can navigate away and the import continues in the background
- Check System Operations → Data Hub → History for status
- The wizard logs failed rows with specific error messages
- You can resume partially completed imports
For very large imports (10,000+ records), consider splitting your file into smaller chunks. This makes it easier to identify and fix issues.
Troubleshooting Import Errors
Common Validation Errors
| Error | Cause | Solution |
|---|---|---|
| Required field missing | Mandatory field not mapped | Map the required field or add data to your file |
| Invalid email format | Malformed email addresses | Clean email addresses before import |
| Date parse error | Unrecognized date format | Use YYYY-MM-DD or MM/DD/YYYY format |
| Number format error | Text in numeric fields | Remove currency symbols, commas from numbers |
| Company not found | Linked company doesn't exist | Import companies first, or create them manually |
File Format Issues
- Encoding errors: Save your CSV as UTF-8 encoding
- Delimiter issues: Use comma-separated values, not semicolons
- Extra columns: Remove blank columns from your spreadsheet
- Merged cells: Unmerge all cells in Excel before exporting
After Import Fixes
If some rows failed to import:
- Go to Data Hub → History and find your import
- Download the error log to see which rows failed and why
- Fix the issues in your original file
- Re-import only the failed rows with 'Skip Duplicates' enabled
Best Practices for CRM Migration
- Start with a small test import (50 to 100 rows) to verify mappings work correctly
- Import in order: Companies, then Contacts, then Deals, then Invoices
- Back up your source data before making changes
- Use consistent naming for companies to ensure proper linking
- Clean and deduplicate data in your spreadsheet before importing
- Document your field mappings for future reference
- Assign a team member to review and verify imported data
You cannot automatically undo an import. For large migrations, run a test import in a separate workspace first.
Quick Reference
Start import: System Operations → Data Hub → Import
View import history: System Operations → Data Hub → History
Download error log: Data Hub → History → [Import] → Errors
Supported formats: CSV, XLSX, XLS
Max file size: 50 MB per file
Recommended batch: 5,000 rows per import
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