An electronic mail (email) system generates an email user interface display, with a timeslot actuator, for composing an email message. Actuation of the timeslot actuator is detected and the email system accesses available timeslots from a calendar system corresponding to the user. User selectable display elements, corresponding to each available timeslot, are displayed on the email user interface display, along with message content. When a user selectable display element corresponding to an available timeslot is selected, the email message content is populated with a selectable timeslot element, corresponding to the available timeslot, that can be sent to recipients in the email message.