How to Mail Merge in Word 365: A Step-by-Step Guide

To mail merge in Word 365, create or open a recipient list, choose a merge type from the Mailings tab, connect the list, insert fields such as names or addresses, preview the results, and select Finish & Merge. The merge combines one Word document with many records so each recipient gets a personalized letter, email, envelope, or label. Before starting, check that your list is complete and saved, and decide what you want to produce.

What You’ll Need

Word for Microsoft 365. The instructions below use the Windows desktop app. Word for Mac has a similar Mailings tab, though some labels and dialog layouts can differ slightly.
A recipient list. You can use an Excel workbook, a CSV file, or a supported contacts list. An Excel file is convenient when you need to sort or check the data first.
A clear header row. Give each column a distinct heading, such as FirstName, LastName, Email, and StreetAddress. Each row beneath the headings should contain one recipient.
A destination and a test record. Decide whether the result should be a document, printed item, or email. Keep a sample recipient handy so you can check a test merge before sending or printing.

Step-by-Step

Prepare and save the recipient list. In Excel, put the field names in the first row and one person or organization on each subsequent row. Keep each kind of information in its own column: do not put a full name in one column if you need to address people by first name. Remove blank rows, merged cells, totals, and notes from the data table. Save and close the workbook before connecting it to Word; this helps avoid file-locking or stale-data problems. If you use CSV, check that the columns are separated correctly and that special characters display properly when opened.
Choose the type of merge. Open Word and either create a new document or open the document you want to personalize. On the Windows ribbon, select Mailings > Start Mail Merge, then choose Letters for individualized documents. Choose E-mail Messages for email, or select Envelopes or Labels if those are your intended output. For labels, choose the label vendor and product number when Word prompts you. On Mac, use the Mailings tab and its Start Mail Merge controls; the names are generally similar, but dialogs may be arranged differently.
Connect the recipient list. Select Mailings > Select Recipients > Use an Existing List, browse to your Excel or CSV file, and select it. If Word asks which table or worksheet to use, choose the sheet containing the list and confirm that the first row contains column headings. You can also choose Type a New List to enter a small set of recipients directly, or select Outlook contacts if that option is available in your setup. If the workbook has several sheets, check that you picked the one with the actual records.
Check who will be included. Select Mailings > Edit Recipient List to review the connected records. Clear the check box beside anyone who should not receive the item. Use the sorting and filtering controls in this window to narrow the list—for example, filter a City column to send only to one location. Be careful with filters: a filter left in place can make a successful merge look incomplete because Word is using only the selected records.
Write the shared text. Type the words that should appear in every copy, such as the introduction, main message, and closing. Put the cursor where personalized information belongs. A letter might begin with a greeting, then have a paragraph that refers to a recipient-specific appointment or account. Keep placeholders out of the text as much as possible; insert actual merge fields rather than typing labels such as FirstName in the document.
Insert personalized fields. Select Mailings > Insert Merge Field and choose the matching column heading, such as FirstName or AppointmentDate. Add punctuation and spaces around fields as needed. For example, a greeting can contain a salutation field followed by a first-name field and a comma. You can insert the same field more than once. For common address or greeting formats, use Address Block or Greeting Line on the Mailings tab, then use the matching or format options to align the Word labels with your column headings. If you use labels, set up the first label and select Update Labels so Word copies the layout to the rest.
Preview actual records. Select Mailings > Preview Results. Use the previous and next record arrows beside the preview control to inspect several recipients, including the first, a middle record, and the last. Check that names, spacing, punctuation, dates, and addresses look right, and that long values do not break the layout. Turn Preview Results off to return to the merge-field view if you need to edit the document. For labels, also confirm that each record appears in the expected label position.
Finish the merge to the right destination. Select Mailings > Finish & Merge. Choose Edit Individual Documents to create a separate combined document you can inspect and save; select all records or a specific range in the dialog. Choose Print Documents to send the merged output to a printer. For an email merge, choose Send E-mail Messages, select the column containing email addresses in the To box, enter a subject line, and choose a mail format. Word creates a separate message for each selected record rather than one message with all recipients visible to each other.
Review before sending or printing. If you chose Edit Individual Documents, Word opens a new file containing the merged copies. Read through it, check page breaks and formatting, and save it under a new name so you retain the reusable template. For email or printing, first run a small test with your own address or a few records, if practical. Confirm the recipient count and output before completing a large mailing.

Common Mistakes

Using unclear or inconsistent headings: Word displays Excel column headings as merge-field names. Headings such as Column1 or repeated names make it easy to insert the wrong field. Rename the headers before connecting the list, and keep them unique.

Leaving out records unintentionally: A blank row in the middle of the data, a recipient-list filter, or unchecked records can affect who appears. Review Edit Recipient List and compare the expected record count with the preview and finished document.

Typing field names instead of inserting fields: Text that looks like «FirstName» is not necessarily a live merge field. Insert fields using the Mailings tab. If a field displays its name in angle brackets during editing, preview the results to see whether it is connected properly.

Trusting formatting without checking it: Excel formatting for dates, currency, and postal codes may not transfer as expected. Postal codes with leading zeros are especially easy to damage if Excel treats them as numbers. Store postal codes as text in the source data, and inspect dates and numbers in Word’s preview.

Sending straight to everyone: A wrong email column, outdated address, or awkward layout can affect a whole mailing. Preview multiple records and send a test before selecting the full recipient group.

Tips

Use one source column per piece of information. Separate FirstName and LastName fields make it easier to write natural greetings. Keep addresses split into sensible parts if you need to rearrange them in a label or letter.
Keep the template reusable. Save the Word document before and after connecting the list. The template retains the merge fields, so you can reconnect an updated list later using Mailings > Select Recipients.
Match fields for address blocks. If Address Block leaves out a name or uses the wrong column, open its matching-fields options and map the source headings to the expected address fields. Correct the source headers too, if they are ambiguous.
Check date and number display in Word. If a date appears as a serial number or an unexpected format, right-click the merge field and choose Toggle Field Codes. You can add a date-format switch to the field—for example, a format equivalent to “MMMM d, yyyy”—then update the field and preview again. The field-code menus and keyboard shortcuts can differ between Windows and Mac, so using the context menu is often easiest.
Keep email subject lines specific. Use a subject that clearly identifies the message, and verify that the address column contains valid email addresses. Word’s email merge depends on a configured desktop email setup; availability and behavior can vary with Outlook version and account configuration.
Use a test copy for layout changes. When adjusting labels or a multi-page letter, merge a few records to a new document first. It is easier to spot overflow, blank pages, or unexpected line breaks before printing a full batch.

Troubleshooting

The fields show headings or placeholder text instead of recipient values. Turn on Mailings > Preview Results. If the preview still does not change, check that a recipient list is connected, that the correct worksheet is selected, and that the inserted field matches a column heading. Reconnect the workbook if the source file was moved or renamed.

The wrong people appear, or some are missing. Open Mailings > Edit Recipient List and inspect the check boxes, sort order, and filters. Check the selected worksheet for blank rows or data stored outside the main table. Clear filters if you need every record, then preview the beginning and end of the list.

Dates, amounts, or postal codes look wrong. Check the value in the source workbook first. For dates and amounts, use a Word field format when the source formatting is not carried over. For postal codes, store the original value as text—changing a cell to a text format after Excel has already removed leading zeros will not restore them. Correct the source and reconnect or refresh the list, then preview again.

The email merge will not send. Confirm that the To field is mapped to the email-address column and that your desktop email account is set up and working. Try a single test recipient. If Word cannot hand off the messages, check the current support and configuration requirements for your installed Outlook version, or create the merged documents and use an approved sending method instead. Do not assume an email merge was sent unless you can confirm the messages in the sending account.

Labels are misaligned or repeated incorrectly. Confirm the label vendor and product number under the label setup options, then check printer paper size and scaling. In the label document, use Update Labels after changing the first label. Print a test page on plain paper and hold it against a label sheet before printing the full batch.

Frequently Asked Questions

Can I use an Excel spreadsheet for a Word 365 mail merge?
Yes. Save the workbook with one header row and one recipient per row, close it, and connect it through Mailings > Select Recipients > Use an Existing List. Choose the worksheet containing the records.

Can Word 365 send personalized emails?
Yes. Choose E-mail Messages as the merge type, connect a list with an email-address column, and use Finish & Merge > Send E-mail Messages. Word sends individual messages, and a configured desktop email account is generally required.

Can I edit each merged letter before printing?
Yes. Choose Finish & Merge > Edit Individual Documents. Word creates a new document with the selected recipients’ details filled in. Review and save that file before printing.

Why does Word show a date as a number?
The date’s underlying value may have come through without the display format you expected. Apply a date format to the merge field in Word, or adjust the source data and preview again. Always check the finished output, not just the Excel cell format.

Does mail merge work in Word for Mac?
Word for Mac includes mail merge features and uses a similar Mailings workflow. Some dialogs or options may look different from Windows. If a command is not where expected, check the Mailings tab and the current Word for Mac help for that feature.

How do I reuse a mail merge?
Save the Word template with its merge fields. For the next mailing, update the source list or connect a new one using Mailings > Select Recipients, then preview the records again before finishing the merge.

Try it: the Date Difference Calculator: days, months, years and weekdays between two dates, with the DATEDIF formulas.

More in How-to basics

Sources: Function behaviour and menu paths: Microsoft Support documentation for Excel. Method & sources

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