Mail merge lets you send the same email to many people with each one personalized with their name, company, or other details

Mail merge pulls information from a spreadsheet — names, email addresses, company names, or any other data — and inserts it into an email template. Instead of writing 50 individual emails, you write one template with placeholders, connect it to your data, and the mail merge tool fills in the blanks for each recipient. The result is a batch of personalized emails that look like you wrote each one separately.

The most common setup uses Gmail with Google Sheets, or Outlook with an Excel spreadsheet. Both are free if you already have those accounts. Other email providers and tools exist, but Gmail and Outlook cover most people's needs. The process takes about 15 minutes to set up the first time, then a few minutes for each campaign after that.

Key Takeaways

  • Mail merge works by pulling names and other details from a spreadsheet and inserting them into an email template, so each recipient sees a personalized message.
  • Gmail requires a free add-on called Mail Merge for Gmail or similar; Outlook has mail merge built into the desktop version but not the web version.
  • Your spreadsheet must have one column per data field (name, email, company) and one row per recipient, with headers in the first row.
  • The email template uses placeholder text in double curly brackets — like {{FirstName}} — that the tool replaces with actual data from your spreadsheet.
  • Always send a test email to yourself first to check that the placeholders are working and the message looks right before sending to your full list.

Setting up mail merge in Gmail

Gmail does not have mail merge built in, so you need to install an add-on. The most widely used is Mail Merge for Gmail, which is free. Go to Gmail, click the grid icon in the top right corner, select "More," then search for "Mail Merge for Gmail." Click the result, then click "Install." You will be asked to give the add-on permission to send emails on your behalf — this is normal and required for it to work.

Once installed, open Gmail and click the three-line menu icon on the left. Scroll down and you will see "Mail Merge" as a new option. Click it to open the mail merge panel on the right side of your screen. From here, you can start a new campaign or upload your spreadsheet.

Before you open the mail merge tool, prepare your Google Sheet. Create one column for each piece of information you want to personalize — typically email address, first name, last name, company, or whatever else you plan to reference. Put the column headers in the first row. Each row below that is one recipient. Make sure the email address column exists; the tool needs it to know where to send each message.

Setting up mail merge in Outlook

Outlook's mail merge feature only works in the desktop version (Windows or Mac), not in Outlook on the web. Open Outlook and go to the "Mailings" tab at the top. Click "Start Mail Merge," then choose "E-mail Messages." This tells Outlook you are sending emails, not letters or labels.

Next, click "Select Recipients" and choose "Use an Existing List." Navigate to your Excel spreadsheet. The spreadsheet should have the same structure as the Gmail version — one column per data field, headers in the first row, one row per recipient. Outlook will read the headers and use them as field names.

Write your email in the message window. Where you want personalized information to appear, click "Insert Merge Field" and select the field name from the dropdown — for example, "FirstName" or "Company." Outlook will insert a placeholder like <<FirstName>> into your message. This is where the actual names will go when you send.

Creating the email template with placeholders

The email template is the message that will be sent to everyone, with placeholders where personalized information goes. Write it as you normally would — subject line, greeting, body, signature. Anywhere you want to insert data from your spreadsheet, use the placeholder format.

In Gmail's Mail Merge for Gmail add-on, placeholders use double curly brackets: {{FirstName}}, {{Company}}, {{EmailAddress}}. The text inside the brackets must match the column header in your spreadsheet exactly, including capitalization. If your spreadsheet column is "First Name" with a space, the placeholder must be {{First Name}}.

In Outlook, use the "Insert Merge Field" button rather than typing placeholders manually. This ensures the field names match your spreadsheet. The placeholder format is <<FieldName>>.

A typical template might look like this: "Hi {{FirstName}}, I wanted to reach out to you at {{Company}} about our new product. Let me know if you would like to schedule a call." When the merge runs, {{FirstName}} becomes "Sarah" for one recipient and "Marcus" for another, and {{Company}} becomes their actual company name.

Uploading your data and testing before sending

In Gmail's Mail Merge for Gmail, click "Upload Spreadsheet" in the mail merge panel. Select your Google Sheet from the list, or upload an Excel file. The add-on will read the headers and show you a preview of how the first email will look with the actual data filled in.

In Outlook, after you insert all your merge fields, click "Preview Results" to see how the email will look with real data. Use the arrow buttons to scroll through a few examples and make sure the names, companies, and other details are appearing correctly in the right places.

Before sending to your full list, always send a test email to yourself. In Gmail, the Mail Merge for Gmail panel has a "Send Test Email" button. In Outlook, click "Finish & Merge," then "Send Email Messages," and choose to send to a single test recipient first. Check that the placeholders were replaced with actual data, the formatting looks right, and there are no typos or awkward line breaks.

Sending the campaign and tracking what was sent

Once you have confirmed the test email looks correct, you are ready to send to your full list. In Gmail's Mail Merge for Gmail, click "Send Emails" in the panel. The add-on will send one email per row in your spreadsheet. Sending 100 emails typically takes a few minutes. Gmail will show you a progress bar and let you know when it is complete.

In Outlook, click "Finish & Merge," then "Send Email Messages." Choose "All" to send to everyone in your list, or "Current Record" if you want to send to just one person. Outlook will send the emails and create a record in your Sent folder showing that the merge was completed.

Both tools keep a log of what was sent. In Gmail, the Mail Merge for Gmail add-on stores a history of your campaigns. In Outlook, the emails appear in your Sent folder as individual messages. If you need to resend to someone who did not receive the email, you can send them a regular email manually or run the merge again with just their row in the spreadsheet.

Common mistakes and how to avoid them

The most common error is a mismatch between placeholder names and spreadsheet column headers. If your spreadsheet has a column called "Company Name" but your placeholder says {{Company}}, the merge will fail or leave the placeholder text in the email. Always double-check that the text inside the brackets matches the header exactly.

Another frequent issue is including the recipient's own email address in the spreadsheet but not using it as the send-to field. Both Gmail and Outlook need to know which column contains the email addresses where the message should go. In Gmail, the Mail Merge for Gmail add-on usually detects this automatically, but you can specify it manually. In Outlook, the email column is selected when you choose your recipient list.

Blank cells in your spreadsheet can cause problems. If a row is missing a first name or company, the placeholder will either show as blank or display an error. Review your spreadsheet before uploading and fill in any missing data, or remove rows for people you do not have complete information for.

Frequently Asked Questions

Can I schedule mail merge emails to send at a specific time?

Gmail's Mail Merge for Gmail does not have a built-in scheduling feature — emails send immediately when you click Send. Outlook's desktop version also sends right away. If you need to schedule, you can use third-party tools like Mailmodo or Zapier that integrate with Gmail or Outlook and add scheduling, but these are not free.

What if I want to send different emails to different groups of people?

Create separate spreadsheets for each group and run the mail merge multiple times with different templates. For example, one merge for customers and another for prospects, each with a different message. This takes a few extra minutes but keeps your campaigns organized.

Can I use mail merge with attachments?

Gmail's Mail Merge for Gmail add-on does not support attachments. Outlook's mail merge does — attach the file to your template email before you start the merge, and it will be included in every message sent. If you need to send different attachments to different people, you will need a more advanced tool.

What happens if someone's email address is wrong in the spreadsheet?

The email will bounce back to you as undeliverable. The mail merge tool will not catch this before sending. Review your email list for typos before uploading, or use a tool that validates email addresses first.

Can I personalize the subject line too?

Yes. In both Gmail and Outlook, the subject line is part of the email template, so you can add placeholders there just like in the body. A subject line like "Hi {{FirstName}}, a special offer for {{Company}}" will personalize for each recipient.