Glossary

What is lead deduplication?

Lead deduplication is finding records that describe the same person or company and merging them into one. Matches are exact, on email or phone, or fuzzy, on a similar name at a similar company. Deduplication matters in outreach because duplicates cause the same person to receive the same message twice.

Published by Sellinger AI. Numbers and settings checked on 24 October 2026 against the fact register. Report an error.

How does matching work?

Match types
Match	Example	Confidence
Exact email	anna@example.com in two records	Very high
Exact phone	The same number in two records	High
Name and company	Anna Petrova at Example Ltd and A. Petrova at Example	Medium, needs review
Name only	Two Anna Petrovas	Low; often different people

Merge or keep apart?

Merge when you are confident it is the same person, and keep the record with the better data as primary. Keep apart when only the name matches. A wrong merge mixes two people's histories, which is worse than a duplicate.

How do you prevent duplicates?

Check imports against existing records before adding them.
Use one source of truth for leads, not several tools with their own lists.
Normalise emails and phone numbers before matching.
Assign accounts to owners so two people do not add the same company.

How Sellinger handles it

Sellinger lists likely duplicate pairs on its Merge Suggestions page, with the reason (an email match, a phone match or a name similarity) and a confidence score; exact email matches score 98% and exact phone matches 95%. You choose the primary lead and merge, or dismiss. CSV imports skip rows that are already in your team. See why a CSV import skips rows.

Common questions

What is a fuzzy match?

A match on similar rather than identical values, such as a name spelled two ways. It needs review.

Can deduplication be automatic?

Exact matches can be merged with confidence. Fuzzy matches should be reviewed by a person.

Do merged leads keep their history?

In Sellinger, the conversation history, profile data, tags and segments come together on the primary lead.

Sources and method

General data practice. Sellinger behaviour from the duplicate leads help article, checked 24 October 2026.