Add reminders to iCal on a Mac and see them beside your events

Two people asking how to add reminders to iCal usually want two different things. One wants an alert before a meeting so the meeting is not missed. The other wants a to-do with a date on it to appear next to the day's events, so the day can be read in one place. The Mac does both, through different mechanisms, and the reason searches on this topic end in confusion is that the two get described with the same word.

Two different things are called a reminder

The distinction is not an Apple invention. The file format that every calendar exchanges data in defines both, as separate components with separate rules.

An alarm is attached to something else. It has an action, such as displaying a message or playing a sound, and a trigger expressed relative to the start or end of the thing it hangs off. The standard's own examples include a trigger of thirty minutes before the start, fifteen minutes before the start, and five minutes after the end. An alarm cannot exist on its own, and it has no state. It fires and it is finished.

A to-do is its own item. It has a due date, a completion state and a percentage complete. It can exist with no date at all. Nothing fires unless an alarm is attached to it, and a to-do that is never completed stays on the list indefinitely.

Those two shapes explain every behaviour that follows. An alert cannot be ticked off, and a task does not vanish when its moment passes.

	Event alert	Dated reminder
Lives in	The event itself	The Reminders app
Has a completion state	No	Yes
Exists without a date	No	Yes
Appears in Calendar as	A notification	A row on the day
Survives its moment	No	Yes, until completed

The app that was called iCal has been named Calendar for many years now, and it is the Calendar app that shows both. What it shows for the second kind is worth being precise about, because it is not all reminders.

Showing reminders in Calendar on a Mac

Apple's Calendar guide, which covers macOS 27 Golden Gate, macOS Tahoe 26 and macOS Sequoia 15, states the mechanism directly. Reminders are shown by selecting the Scheduled Reminders checkbox in the calendar list. If the calendar list is not visible on the left, it is opened from View > Show Calendar List.

The name of the checkbox is the important part. It says scheduled. A reminder with no date is not scheduled, so it is not drawn, and there is no setting that changes that. This is the single most common surprise on the topic: a Reminders app full of items, a checkbox switched on, and almost nothing appearing. The items without dates are working exactly as designed and living exactly where they should.

Where the dated ones land follows the same logic as events.

Reminders scheduled as all day appear in the all-day section at the top of the calendar. Reminders with a time appear next to a specific time in the full-day schedule. Source: support.apple.com

So a task due today with no time sits in the strip above the grid, alongside all-day events, and a task due at three o'clock sits at three o'clock next to whatever meeting is there. Deselecting the same checkbox removes them again, and nothing in the Reminders app is changed by doing so.

Why the all-day strip matters more than it looks

Most tasks are given a date and no time, which means most of them land in the same strip. On a day with two all-day events and six dated tasks, that strip becomes the tallest thing on screen and pushes the actual hours of the day down. This is not a fault, but it does mean the reminders row is worth reviewing rather than accumulating, because an untended list of dated tasks quietly squeezes the part of the calendar that shows where time is going.

Creating a reminder without leaving Calendar

Calendar can create them as well as show them, which removes the usual reason for switching apps.

The route in Apple's guide is to click the create button in the toolbar and then click New Reminder. A title is entered, and the date next to "remind me" is clicked to choose a date. Selecting At a Time turns it into a timed reminder and takes a specific time. Other details, such as notes, images or a priority level, can be added from the same panel.

The list it goes to is worth setting once. The guide notes that a specific Reminders list can be selected for new scheduled reminders, and that without a selection, new reminders go to the default list chosen in the Reminders app. Leaving that unconsidered is how tasks created from the calendar end up in a list nobody reviews.

This is the part of the flow where the two systems genuinely join up. A meeting produces an action, the action needs a day, and both the meeting and the action end up on the same screen without an app switch. The value is not the feature, it is the absence of a decision about where to put things. Anything that makes capture slower than the thought pushes the thought into a note nobody reads again, which is why calendars for the Mac put quick entry behind a single keystroke and parse the date out of ordinary typed text. The Entering events section of the guide covers how a typed or spoken phrase is turned into an event or a task.

Completing, editing and deleting them

Completion is what a to-do has and an alert does not, and it works from Calendar. Selecting the control next to the reminder's name marks it complete, and completed reminders are dimmed rather than removed. Deselecting the same control marks it incomplete again.

Repeating reminders have one rule that catches people out. Apple's guide states that if a scheduled reminder is set to repeat, future instances are dimmed and can be marked complete only after the most current instance is marked complete. So a repeating task cannot be ticked off three weeks ahead. The instances have to be cleared in order, which is a reasonable design for a habit and an annoyance for anyone trying to clear a backlog out of sequence.

Editing depends on the view. In Week or Month view a reminder is opened by double clicking or force clicking it. In Day view a single click opens it. The details panel that opens is the same one used at creation.

Deleting is a right click and Delete, and the guide is specific about what happens next: deleted reminders move to the Recently Deleted list in the Reminders app for 30 days before being permanently deleted. That window is a genuine safety net. A task deleted from the calendar in a hurry is recoverable for a month, from the Reminders app rather than from Calendar.

The alerts on an event are a separate system

Anyone whose actual question was about being warned before a meeting is looking at a different setting entirely, and it lives on the event rather than in a list.

On a Google account the limits are documented precisely. An event can carry its own reminders instead of the calendar's defaults, and the maximum number of those overrides is five. Each one has a method, either an email or a popup, and a number of minutes before the start of the event, valid from zero up to 40,320 minutes, which is four weeks. An event can also simply use the calendar's default reminders instead of defining its own.

Those numbers are worth knowing because they bound what is possible. Five alerts per event is generous for a meeting and restrictive for anyone trying to build a countdown out of alerts. Four weeks is the furthest ahead a single alert can reach, so a reminder needed two months before a deadline has to be a dated task rather than an alert on the event.

The practical division is clean. Use an alert for something that needs attention at a moment relative to an event. Use a dated reminder for something that needs doing and then needs to be marked done.

What still does not show up on the calendar

Three categories stay invisible, and each has a reason.

Reminders without a date are the largest group, and the checkbox name already says why. They are the right place for anything that is genuinely undated, and forcing a date onto them to make them visible turns a list into a stream of items that get pushed to tomorrow every day.

Tasks kept in Google Tasks are a separate service from Apple Reminders, and the Scheduled Reminders checkbox does not reach them. Anyone whose tasks are split across both will see half of them on the Mac calendar, which usually reads as a sync fault and is not one.

Completed reminders are dimmed rather than hidden, which is a display choice rather than an omission, and it means a heavily used day keeps showing yesterday's finished work. That is either useful context or clutter depending on the week.

Which account the reminders live in

One line in Apple's guide explains a set of differences that otherwise look like bugs. The Reminders app can gather lists from several kinds of account, iCloud, Microsoft Exchange, Google, Yahoo and AOL among them, and the guide then states that the features it describes are available when updated iCloud reminders are in use, and that some of them are not available with accounts from other providers.

So a Mac holding its tasks in a Google or Exchange list can behave differently from the documentation without anything being broken. Anything that depends on the newer reminder fields, which is most of what the Calendar integration shows, is written against iCloud lists. The practical consequence is worth acting on once rather than debugging repeatedly: decide which account holds the dated tasks, make that account's list the default, and keep the other providers for lists that are only ever read in the Reminders app itself.

How much of this a calendar surfaces in one place differs by app. Showing dated tasks on the grid and in the sidebar, and creating them without leaving the calendar, is something Mac calendars handle to different depths, and the Features page sets out how tasks, events, travel and weather are arranged on a single screen.

What to change first

Switch on the Scheduled Reminders checkbox in the calendar list, then open the Reminders app and set the default list to one that is actually reviewed, because that decides where everything created from the calendar lands. After a week, look at whether the all-day strip is doing useful work or just growing. If the answer is that tasks, travel and events all need to be legible on one screen, a Mac calendar built around that is the next thing to try, and Caltimate is one of them.