Outlook includes two methods to send messages at a later time: an after sending rule that holds a message in the Outbox for up to 120 minutes or a setting in Message Options to send the mail at a specific time.
I do not recommend delaying messages more than a few days. Some versions of Outlook uses the date you pressed Send as the sent date, not the date it handed the message off to a SMTP server. If the recipient uses a sort by sent date view, they may not see your message. (Test this before using it.)
You can use VBA to send a message when a reminder fires. See Send an email when an Appointment reminder fires for the code. To delay messages sent during specific hours, see "Delay Delivery of Messages Sent at Specific Times"
To schedule recurring message, see Scheduling a Recurring Message
Hold messages for up to 120 minutes
To hold messages for up to 120 minutes, you need to create an "after sending" rule. This rule can apply to all messages or only to messages that meet the conditions you set.
- Open the Rules Wizard and click New rule.
- Select Apply rule on messages I send (at the bottom of the first Rules Wizard screen)
- Select any conditions you want and click Next or just click Next to apply it to all messages you send
- Choose Defer delivery by a number of minutes at the bottom of the Actions list.
- Click on the "a number of minutes" link to select the desired number of minutes to hold the messages.
- Click Next and set up any desired exceptions, then click Next again.
- Enter a name for your rule, turn the rule on and click Finish to finalize the rule.
Using "Do Not Deliver Before"
Outlook can hold mail in the Outbox and send it at a later date. For this to work, you need to have Outlook running at the appointed time. If you use Exchange server and online mode, not cached mode, the message is moved to the outbox on the server, allowing you to close Outlook.
I highly recommend testing this feature before using, so you understand how it works. Testing it beforehand will allow you to see if your email server uses the time you sent it to the Outbox or when Outlook actually sent the message. For more information, see "Send Time" time stamp information is incorrect when you send a delayed delivery message in Outlook (MSKB)
When I Delay Delivery of a message does it get sent from my PC to the server and wait there? Can I close Outlook, log off my PC and it will still get delivered even if I don't log on to my PC again until after the requested delivery date/time?
When you use Delay Delivery, the message is held in the Outbox on your computer, waiting for the scheduled time, so you will need to leave your computer logged in and Outlook open to send it.
There is one exception: when Exchange mailboxes are opened in online mode, the message is held on the server. Note that this is one Exchange feature not supported by Outlook.com, as it only uses cached mode.
If you hold messages to send later, you will receive a prompt from Outlook every time you close Outlook, reminding you that there are messages waiting to be sent.
You cannot disable this alert. It really does have purpose: Anyone who doesn't use Send Immediately or is having connectivity issues appreciates being told Outlook hasn't sent the messages in the Outbox. Use this dialog to stop accidentally closing Outlook.
Tools in the Spotlight
One of the utilities in the MAPILab Toolbox, Email Scheduler allows you to chedule messages to be sent at specific date/times or intervals by setting up a task for each message. MAPILab Toolbox is a set of 18 different add-ins for Outlook.
Schedule Recurring Email schedules email to send later. The maximum number of emails that can be scheduled can be in the hundreds. You can schedule emails that go out hourly, daily, monthly, early, or randomly. The monthly and yearly patterns can be adjusted by a number of days so that schedules like "2nd to last workday of the year" or "3 days after the first Tuesday of every month" can be specified. Works with all Outlook accounts, including IMAP and Outlook.com.
SendLater is a free Outlook add-in e-mail scheduler with recurring email option. Prepare all your email notifications and reminders in advance and schedule their delivery. Re-send email automatically if a reply is not received. Set up repetitive follow-up emails at comprehensive time intervals. When sending recurrent emails, you can set path to CSV file and load recipients from that CSV file automatically. The updated SendLater is fully compatible with the latest Windows 2018 October Update and Microsoft Outlook 2019.
SetDeliveryTime has been created to allow users to set the default value for the "Do not deliver before:" parameter in Outlook.
Use ScheduledSend for Outlook to send emails on a schedule. Set a schedule and recurrence as Outlook appointment and send emails on a later date. The add-in adds a separate calendar where all your scheduled emails are displayed in a familiar fashion.
Email and presentation tracking, email templates, and Salesforce integration for Outlook 2010, 2013, & 2016 on Windows.
Scheduling a Recurring Message
Sending and Retrieval Tools for Outlook
Mass Mail Tools for Outlook
Compose Tools for Outlook
Duplicate Remover Tools for Outlook
Mail Tools for Outlook - Outlook mail tools that don't fit in any of the above categories.
Content Control Tools
Security Tools -- Some of these also provide message tracking.
Signature Tools -- including random quotes
From Outlookcode.com: Using Microsoft Outlook to Schedule Report Transmissions