How can you get an audible notification from a reminder?

Have Siri announce notifications

Siri can automatically announce incoming notifications from apps like Messages and Reminders. Siri automatically enables app notifications for apps that use time-sensitive notifications, but you can change the settings at any time.

To learn more about time-sensitive notifications, see Set up a Focus on iPhone.

1. Go to Settings > Siri & Search > Announce Notifications, then turn on Announce Notifications.
2. Tap an app you want Siri to announce notifications from, then turn on Announce Notifications.
3. For some apps, you can also choose whether to announce all notifications or only time-sensitive notifications.

For apps where you can send a reply, like Messages, Siri repeats what you said, then asks for confirmation before sending your reply. To send replies without waiting for confirmation, turn on Reply Without Confirmation.

An example of the Health App Notification is given below. You may do the same thing for the Reminders too.