Setting a reminder in Outlook takes two clicks after you create an event or email
Open the calendar event or email you want to be reminded about. In the event details, look for the Reminder dropdown — it usually shows a default time like "15 minutes before". Click that dropdown and pick when you want the alert: 5 minutes, 15 minutes, 1 hour, 1 day before, or a custom time you set yourself. The reminder will pop up on your screen at that moment, and the event stays flagged until you dismiss it.
If you are setting a reminder on an email instead of a calendar event, the process is almost identical. Right-click the email, select Follow Up, then choose Add Reminder. Pick your timing the same way. Outlook will alert you at the time you chose, and the email stays marked as a follow-up task until you clear it.
Reminders work across all Outlook versions — desktop, web, and mobile — so an alert you set on your computer will also show on your phone if you are signed into the same account.
Key Takeaways
- Calendar event reminders are set in the event details dropdown and default to 15 minutes before the event starts.
- Email reminders use the Follow Up menu and work the same way, alerting you at a time you choose.
- You can set custom reminder times beyond the preset options by selecting "Custom" in the dropdown.
- Reminders sync across your devices, so an alert set on your desktop will also appear on your phone.
- Dismissed reminders do not come back unless you manually reset them on the event or email.
How to set a reminder on a calendar event
Create or open a calendar event in Outlook. In the event window, find the Reminder field — on the desktop version it appears in the right panel under the event title. Click the dropdown next to the current reminder time. You will see preset options: 5 minutes, 15 minutes, 30 minutes, 1 hour, 1 day, 1 week, or 2 weeks before the event.
Select the time that works for you. If none of the presets fit, click Custom at the bottom of the dropdown and type in your own number of minutes or hours. Once you pick a time, save the event by clicking Save or Done. Outlook will send you an alert at that exact moment before the event starts.
You can set multiple reminders on the same event if you want alerts at different times. Click the plus icon next to the Reminder field to add a second or third reminder. This is useful for important meetings where you want a heads-up an hour before and another 15 minutes before you need to join.
How to set a reminder on an email
Right-click the email you want to follow up on. A menu will appear with several options. Select Follow Up, then choose Add Reminder. A small window opens where you can pick when you want to be reminded — the same preset times explore as with calendar events.
Alternatively, click the email once to select it, then look for the Follow Up button in the toolbar at the top of the screen. Click the dropdown arrow next to it and select Add Reminder. The reminder options appear, and you choose your timing the same way.
When the reminder time arrives, Outlook displays a notification on your screen and marks the email with a flag icon. The email stays flagged until you manually clear it by right-clicking and selecting Mark Complete or removing the flag.
Setting custom reminder times for specific needs
If the preset reminder times do not match what you need, use the Custom option. Open the Reminder dropdown on your event or email and select Custom at the bottom. A text field appears where you can type any number of minutes or hours you want.
For example, if you have a dentist appointment at 2 p.m. and want a reminder at 1:30 p.m., type "30 minutes" in the custom field. If you want to be reminded 3 days before a project important date, type "3 days" or "72 hours". Outlook accepts most common time formats, so you can write "2 hours", "120 minutes", or "1 day" and it will understand.
Custom reminders are especially useful for events that need more lead time than the standard options provide — like a reminder a week before a birthday, or a reminder the morning of a flight that leaves in the afternoon.
Where reminders appear and how to manage them
When a reminder time arrives, Outlook displays a notification box in the corner of your screen (on desktop) or as a push notification (on mobile). The notification shows the event name or email subject and gives you options to dismiss it, snooze it, or open the item.
If you click Snooze, Outlook will remind you again in 5 minutes by default. You can change the snooze time by clicking the dropdown next to Snooze — options usually include 5 minutes, 15 minutes, 1 hour, or 1 day. This is useful if you are not ready to act on the reminder yet but do not want to forget about it.
Dismissed reminders do not return unless you manually reset them. If you dismiss a reminder by mistake, open the event or email again and set a new reminder time. There is no way to recover a dismissed reminder, so be careful when clicking the X to close the notification.
Reminders across Outlook on different devices
If you use Outlook on your desktop, phone, and web browser, reminders sync across all of them. When you set a reminder on a calendar event in the desktop version, that same reminder will trigger on your phone and in the web version at the same time.
This means you do not have to set reminders separately for each device. Sign into the same Microsoft account on all your devices, and Outlook keeps your reminders in sync automatically. If you dismiss a reminder on your phone, it will not appear again on your desktop — the dismissal syncs too.
The one exception is if you are using an older version of Outlook or a third-party email client that does not fully sync with Microsoft's servers. In that case, reminders may not transfer between devices. Check your Outlook version and account settings to make sure you are signed into the same Microsoft account everywhere.
Troubleshooting reminders that do not appear
If you set a reminder but did not see an alert at the scheduled time, check a few things. First, make sure Outlook was actually running when the reminder time arrived — if you closed the program, the notification may not have shown. Restart Outlook and check if the reminder appears.
Second, check your notification settings. On Windows, go to Settings > System > Notifications and make sure Outlook is allowed to send notifications. On Mac, open System Preferences > Notifications and check that Outlook has permission. On mobile, check your phone's app notification settings for Outlook.
Third, verify that the reminder was actually saved on the event or email. Open the item again and look at the Reminder field — if it shows "None" instead of a time, the reminder did not save. Set it again and click Save. If reminders still do not work after checking these steps, try signing out of Outlook and signing back in to refresh your account connection.
Frequently Asked Questions
Can I set a reminder for after an event starts?
No. Outlook only allows reminders before an event or email follow-up time. If you need to be reminded about something after it happens, create a separate task or calendar event for that follow-up time instead.
What happens if I snooze a reminder and then close Outlook?
The snoozed reminder will still trigger at the snooze time you set, even if Outlook is closed. When you reopen Outlook, the notification will appear. If Outlook stays closed past the snooze time, you may miss the alert.
Can I set different reminders for the same event on different devices?
No. Reminders sync across all your devices, so if you set a reminder on your desktop, it will be the same on your phone and web version. You cannot have different reminder times for the same event on different devices.
Do reminders work if my computer is in sleep mode?
On Windows, Outlook can wake your computer to show a reminder if you have that setting enabled. On Mac, reminders may not appear if the computer is asleep. Check your Outlook settings under Options > Advanced to see if "Wake computer for reminders" is turned on.
What is the difference between a reminder and marking an email as important?
A reminder sends you an alert at a specific time you choose. Marking an email as important just adds a flag or star to the email so it stands out in your inbox, but does not trigger any notification. Reminders are better for time-sensitive follow-ups.