How to Find the Same Username on Different Email Domains in a List

To find the same username on different email domains, group the addresses by the text before the @ and look for names that appear on two or more domains. The shared username email finder does this for a pasted column or an uploaded list, leaves out role names like info and sales, shows each group, and says whether the domains are personal or company.

A shared name is a clue, not proof of one person.

Why the same name shows up on several domains

People sign up with a Gmail address one month and an Outlook or work address the next. A list built from several sources then holds the same person twice under different addresses, and exact-match duplicate removal never catches it because the domains differ.

The by-hand way

1. Cut the text before the @ into its own column and lower-case it.
2. Sort that column and look for names that repeat.
3. For each repeat, check whether the domains differ.
4. Judge by hand which repeats are one person.

Sorting a few hundred rows is fine. On a large list you will miss groups, and you have to ignore info and sales yourself.

Step 1: load the addresses

Upload the list as a CSV or .xlsx, or paste the cells with the header row first. It needs a column of email addresses.

Step 2: find the shared names

Press Find the shared names.

Step 3: read the groups

Each group shows the name and every address that uses it. Personal-only groups are the likeliest to be one person. Download the groups, keep the address you want for each person, then check what is left.

For exact repeats of the same address, use remove duplicate emails. For names that differ only by Gmail dots, see the Gmail address normalizer.

What this check cannot do

• A common name such as sam or alex will match many different people.
• It finds shared names, not people with different names on different domains.
• It reads address text only and does not check mailboxes.
• Whether to merge or keep both is your decision.

For a related duplicate case, see plus addressing and trial abuse.

Then check the mailboxes

Once each person has one address, check that the address works. You can upload the file to the verify page and get the first 100 checks free after a Google sign-in, no card needed. Each address is marked valid, risky or invalid with a reason, and the check sends nothing to the people on it. List cleaning and bulk email verification cover regular or large jobs.

Try it now

Paste your list into the shared username email finder.