Send mass email to leads in Salesforce.
Lead Object > Tools > Mass email Leads
Click Go to get the list of all the users. You can also create New View and filter the users as required. Select the lead you want to send the mass email and next.
Select the email template from folder you want to use to send mass email and next.
Store an activity for each message: Select by default
Enter the Mass Email Name.
Delivery Options: When you want to schedule the email. You can send the email right now by selecting Send now option or you can schedule the mass email on specific date and time and time zone.
Click Send and then finished