How to review duplicate leads before an import

Preserve the original

Work on a copy and label the batch clearly. Use a review column to record proposed merges before removing rows. Keep the original until the import has been checked. This provides a way to explain decisions and recover information if two contacts were incorrectly treated as the same person.

Normalize for comparison

Trim spaces in emails and use a consistent phone format for comparison. Retain original values where useful. Compare several fields together instead of relying on name alone. Shared office phone numbers and generic inboxes can legitimately appear on multiple records, so an exact match is a prompt to inspect context.

Resolve conflicts individually

Check which details are current and where they came from. Do not automatically keep the row with more filled cells. Preserve useful conversation notes and flag contradictions. If identity remains uncertain, keep records separate until you have evidence to combine them. A reversible review process is better than an unexplained destructive merge.

Test the destination behavior

Do not assume an importer merges duplicates automatically. Inspect a small fictional batch first. For recurring workflows, track source records that have already been submitted. Spreadsheet preparation and protection against repeated submissions solve different problems, and both matter when the same source can send a contact more than once.