Detecting duplicate contacts
How Nexcal detects duplicate contacts when creating and importing them, and how you can clean up duplicates in your source file.
Last reviewed: 2026-07-22
Detecting duplicate contacts
Duplicate contacts arise easily, for example when the same person appears in several source files or a list is imported more than once. Nexcal helps you detect duplicates before they lead to duplicate calls.
How Nexcal detects duplicates
When importing and creating contacts, Nexcal compares the records, in particular by phone number. If a record is recognized as a possible duplicate, Nexcal points this out in the import summary or rejects the affected record.
Nexcal does not delete existing contacts on its own. The duplicate detection only reports or prevents duplicate creation; you decide how to proceed.
Cleaning up duplicates
- Review the notes in the import summary.
- Correct the source file by removing duplicate rows or standardizing phone numbers.
- Import the cleaned file again.
- Check your lead lists so the same contact does not appear more than once in the same list.
Hinweis: A consistent phone number in international format makes duplicate detection much easier. See formatting phone numbers correctly.
What duplicate detection does not do
Detection applies to creating and importing contacts. Nexcal does not automatically exclude a contact recognized as a duplicate from all future campaigns. Whether a contact is called depends on which lead lists it is part of and which campaigns those lists are assigned to.
Common questions
Does Nexcal delete duplicate contacts on its own?
No. Nexcal reports detected duplicates or rejects the affected records during import. You decide whether and how to clean up a contact.
How does Nexcal recognize a duplicate?
The comparison is based in particular on the phone number. A consistent notation in international format increases the hit rate of detection.
How do I avoid duplicates in a lead list?
When adding, check whether a contact is already in the list. This prevents the same contact from being called more than once in a campaign.