AleksandarGeorgiev/Getty Images You can do a mail merge in Microsoft Word and Excel to create personalized documents for many recipients at once. You can import an Excel data table into Word to customize your template with names and addresses. Mail merge helps you quickly create auto-personalized letters, envelopes, labels, and more. . It's surprisingly easy to set up a mail merge, which lets you create seemingly personalized communication for a large number of recipients without creating each message by hand. To mail merge a document — like a letter, envelope, printing label, or email — all you need is Microsoft Word and Excel, plus all the names and addresses you want to merge.