Click here to install the Mail Merge add-on in Google Docs
From the Add-ons menu in the Google Sheet, choose Mail Merge with Scheduler > Create Mail Merge Template.
From the Add-ons menu in the Google Sheet, choose Mail Merge with Scheduler > Import Google Contacts
Choose a Google Contacts group from the dropdown to import the associated contacts into the Mail merge sheet.
To include one or more files from Google Drive, click Add File Attachments from the Mail Merge menu.
Use the File Picker opens to select one or more files from Google Drive to attach them to your merged emails.
(Optional) Add the date and time in the Scheduled Date column of the Mail merge sheet to send them at a later date.
Compose a draft in Gmail, you can include add variable fields from the spreadsheet using the {{column name}} notation.
Select your Gmail alias and the sender's name. All the other fields are optional. Click Continue.
Select the Gmail draft and click the Run Mail Merge button to start the mail merge process.
By Amit Agarwal
The best Mail Merge program for Gmail to send personalized emails to multiple people. You can include individual attachments for each recipients.
Tech columnist, geek and founder of Digital Inspiration