There are two parts to a mail merge in Microsoft Word: the data document and the data source. The data document defines how the finished document (the mail merge) will look, and includes layout and styling. The data source holds all the data that is placed into the finished document, such as names and addresses.
There are two kinds of data document. For the first kind, each data record in your data source will create its own document. For example, if you were mailing a press release to all your customers, each customer would get one document. The second kind of data document includes information from multiple records in the data source, all in the same document. Think of catalogues and directories as being examples of this kind.
When you start the Mail Merge process, you need to decide what kind of data document you are working with. Click the Mailings tab and then click Start Mail Merge.
Letters, e-mail messages, and envelopes use one record per output document, while labels and directories use multiple records for each output document.
After you’ve chosen what kind of data document to create, you will need to select what your data source is. To keep things simple, we’re going to use an Excel spreadsheet that holds a list of customers and their details, namely:
- first name
- last name
- address line 1
- address line 2
- town
- county
- postcode
The spreadsheet looks something like this:

Click Select Recipients in the Start Mail Merge group (on the Mailings tab). Because we already have data prepared in our Excel spreadsheet, we’ll select Use Existing List.
Find the spreadsheet, select it and then click Open. In the next window, select what sheet in the workbook your data is in. Click OK. It looks like this action has done nothing, but actually Word has detected what data is in the spreadsheet and has made available the Insert Merge Field command button in the Write & Insert Fields group. If you now click that, you can select from the list of data columns in the spreadsheet. Whatever field you select will be inserted into your data document where the cursor is positioned.
For example, you might want to use the “Dear” salutation in your letter, followed by the customer’s first name.
The mail merge tools in Word are quite powerful, and include such facilities as being able to insert address blocks, defining how the salutation line looks, etc. We’ll cover those in more depth in later tutorials, but for now just get a feel for how the data document works. Basically, you are structuring your document and inserting fields from your spreadsheet (or other data source) in the right place.
When you have finished preparing your data document, it’s time to perform the mail merge itself. Clicking on the Finish & Merge command in the Finish group presents three options.
When you choose one of the selections, the data document you’ve prepared is merged with the actual data in the spreadsheet. Real data from your spreadsheet is placed in all the places where you inserted a merge field.