How to Find Duplicate Contacts With Different Email Addresses

To find the same person under different email addresses, match rows by name and company instead of by email. Excel's Remove Duplicates, most import tools and HubSpot's automatic check all compare the address, so ana.silva@northwind.example, ana.silva.home@gmail.com and asilva@oldemployer.example stay three contacts. Normalize the names (case, accents, titles, middle names), normalize the company (drop Inc, LLC, GmbH, or use the work domain), group rows that share both, keep one address per person and set the rest aside with a note saying which row they duplicate.

The free duplicate contact finder does this in your browser and keeps the extra rows in their own file. Here is the method, so you can do it by hand or check the result.

Why it matters

A person who appears three times in a sequence gets three "personal" cold emails in a day, which reads as spam and invites a complaint. In a newsletter list, they get the same issue twice. And one of the addresses is often from a previous job, so it bounces. Merged lead lists, enrichment waterfalls that return several candidates, CRM imports and event sign-ups are the usual sources. If you are merging files right now, our guide to merging lead lists without duplicates covers the email-level part; this post is the person-level part.

Step 1: remove exact repeats first

Start with the easy cases so the person-level matching has less to do:

• Lower-case and trim every address. Ana.Silva@Northwind.example and ana.silva@northwind.example are one.
• For Gmail, dots and +tags reach the same inbox, so ana.silva+news@gmail.com and anasilva@gmail.com are one. Google describes the dots rule in Gmail Help, and our post on Gmail dots and plus duplicates covers when to apply it.

Remove duplicate emails handles both.

Step 2: normalize names and companies

Matching fails on formatting long before it fails on logic. Before comparing:

Field	Normalize	Example
Name	Lower-case, strip accents, drop titles (Dr, Mr, Ms) and suffixes (Jr, III), drop middle names and initials	Dr. Ana M. Silva Jr. to ana silva
Company	Lower-case, drop legal suffixes (Inc, LLC, Ltd, GmbH, SA) and punctuation	Northwind, Inc. to northwind
No company	Use the domain of the work address	ana@northwind.example to northwind.example

Freemail domains (gmail.com, outlook.com, yahoo.com) never stand in for a company. Otherwise every Ana Silva with a Gmail address would become one person.

Step 3: group by name plus company

Rows with the same normalized name and the same company are one person. In Excel or Google Sheets:

1. Add a key column: =LOWER(TRIM(first))&"|"&LOWER(TRIM(last))&"|"&company_clean.
2. Add a count: =COUNTIF(key_range, key_cell).
3. Filter for counts above 1 and sort by key. Each block is one person.

Don't match on name alone. Two Mia Chens at different companies are two people, and common names collide fast in a list of thousands. The duplicate contact finder only groups same-name rows with no company in common if you turn on its name-only option, and then you should read the duplicates file before deleting anything. The reverse mistake exists too: at a big company, two people can share a name. Glance at job titles inside each group.

What HubSpot does

HubSpot's deduplication article (updated 2 October 2026) says new contacts are checked for "a matching value in the Email property", so a new address makes a new contact. Its separate Manage duplicates tool (updated 23 October 2026) compares "First Name, Last Name, Email address, IP country, Phone number, Zip Code, and Company Name" daily and suggests pairs to merge. Managing individual duplicates needs a Professional or Enterprise subscription, and bulk management needs Data Hub Professional or Enterprise. If you don't have those, clean the file before it is imported; our post on cleaning HubSpot contacts covers the export and re-import.

Step 4: pick the address to keep

For each person, keep one send address. A sensible order:

1. The work address at the company in the row, if it verifies.
2. A work address at a different company only if the row's company is out of date and that one is current.
3. A personal address if there is no working company address and you have a reason to use it.

Don't delete the others. Move them to a second file with a duplicate_of column, so an unsubscribe on any of them can still be applied to the person. Our post on a lead with multiple email addresses goes through the hard cases (aliases, catch-all domains, rebrands).

Step 5: verify the kept addresses

The old-job address is the one most likely to be dead, and you can't always tell which one that is from the file. Upload the kept rows on the verify page. If a kept address comes back invalid, try the person's next address from the duplicates file. Catch-all domains and Microsoft consumer mailboxes can't always be confirmed and come back risky, which means unconfirmed, not bad.

Where SimpleVerifier fits

The duplicate finder is free and runs in your browser. For the mailbox check, the first 100 checks are free with a Google sign-in. Pro is $39 a month with the first 100,000 checks a month at full speed, then slower, never cut off. See pricing.