Avoid sending the same message several times to the same recipient by removing duplicates from your list. Use Google Sheets’ data cleanup function or detect duplicates with conditional formatting and manually remove them.
In this article, we demonstrate how to remove email address duplicates.
Use Google Sheets’ data cleanup function
Google Sheets has a built-in data cleanup function that can remove duplicate rows.
- Open the Google Sheets that contain your mail merge.
- On the menu bar, go to Data > Data cleanup > Remove duplicates.
A dialog box displays options for duplicate removal.
- Choose the column that you want to verify for any potential duplicates. To check the email address column, select Column A.
- Click Remove duplicates.
Google Sheets scans the Email Address column and removes all subsequent occurrences of the duplicates.
Manually detect and remove duplicates
To manually detect and remove duplicates, you can use conditional formatting to make this process easier.
- Open the Google Sheets that contain the mail merge for which you want to remove duplicates.
- Select Format > Conditional formatting.
The Conditional format rules sidebar appears on the right-hand side of the sheet.
- Enter the range to which you want to apply the condition. In this example, we want to apply the range A1:A106 where A is the Email Address column and 1 to 106 is the range containing each email address.
- Open the Format cells if… drop-down and select Custom formula is.
- Enter the formula: =COUNTIF(A:A,A1)>1
This formula highlights all the duplicates in the range.
- Click Done.
Google Sheets highlights all duplicate email addresses. You can now easily see all the duplicates and manually remove them.