Create, read, and manage calendar events and reminders using EventKit and EventKitUI. Use when adding events to the user's calendar, creating reminders, setting recurrence rules, requesting calendar or reminders access, presenting event editors, choosing calendars, handling alarms, observing calenda

EventKit Use EventKit for calendar and reminder authorization, CRUD, recurrence, alarms, and system editors. Contents [Availability]( availability) [Setup]( setup) [Authorization]( authorization) [Creating Events]( creating events) [Fetching Events]( fetching events) [Reminders]( reminders) [Recurrence Rules]( recurrence rules) [Alarms]( alarms) [EventKitUI Controllers]( eventkitui controllers) [Observing Changes]( observing changes) [Common Mistakes]( common mistakes) [Review Checklist]( review checklist) [References]( references) Availability iOS 17+: Use granular full/write only request methods; legacy requestAccess(to:) no longer prompts and throws. The system event editor can create an event without app calendar access. For iOS 10–16, guard those APIs, use the legacy request plus NSCalendarsUsageDescription / NSRemindersUsageDescription ; EventKitUI may also need NSContactsUsageDescription . iOS 26+: The typed EKEventStore.EventStoreChanged / .changed message is available behind a guard. Keep EKEventStoreChanged for earlier systems. Setup Info.plist Keys Add the usage description for the access path selected in [Authorization]( authorization). Do not request broader access merely to simplify the setup path. The authorization free system editor path needs no calendar usage string. Direct writes need write only or full access; reads need full access. Reminders have only full access. Event Store Create a single EKEventStore instance and reuse it. Do not mix objects from different event stores. Authorization Request the narrowest access that matches the feature. Apply the versioned request path in [Availability]( availability). Key Access Level NSCalendarsFullAccessUsageDescription Read + write events NSCalendarsWriteOnlyAccessUsageDescription Direct write only event creation NSRemindersFullAccessUsageDescription Read + write reminders Full Access to Events Call try await eventStore.requestFullAccessToEvents() when the app needs to read, edit, delete, or fetch calendar events. Write Only Access to Events Use when your app only creates events (e.g., saving a booking) and does not need to read existing events. Call try await eventStore.requestWriteOnlyAccessToEvents() before direct EventKit writes that do not use EKEventEditViewController . Write only access can create events but cannot fetch calendars or events, including app created events. Use full access for later query, verification, modification, or sync. Full Access to Reminders Call try await eventStore.requestFullAccessToReminders() before reading, creating, editing, or deleting reminders. Checking Authorization Status Use EKEventStore.authorizationStatus(for: .event) or .reminder before work. Handle .notDetermined , .fullAccess , .writeOnly , .restricted , .denied , and @unknown default ; only .fullAccess supports event/reminder reads. Creating Events Setting a Specific Calendar Adding Structured Location Fetching Events After the full access gate in [Authorization]( authorization), use a date range predicate to query events. The events(matching:) method returns occurrences of recurring events expanded within the range. Event predicates are capped to a four year span, and events(matching:) / enumerateEvents(matching:using:) are synchronous and return only committed events. Fetching a Single Event by Identifier Reminders Creating a Reminder Fetching Reminders Reminder fetches are asynchronous and return through a completion handler. Completing a Reminder Recurrence Rules Use EKRecurrenceRule to create repeating events or reminders. Simple Recurrence Complex Recurrence Editing Recurring Events When saving changes to a recurring event, specify the span: Alarms Attach alarms to events or reminders to trigger notifications. For reminder geofences, put an EKStructuredLocation and .enter / .leave proximity on an EKAlarm , then add it to the reminder. See [references/eventkit patterns.md](references/eventkit patterns.md) for the full location based reminder pattern. EventKitUI Controllers EKEventEditViewController — Create/Edit Events Present the system event editor for creating or editing events. On the authorization free path in [Availability]( availability), the editor runs out of process with its own calendar access. Do not inspect the dismissed controller to learn what was saved; refetch only with separate full access. EKEventViewController — View an Event EKCalendarChooser — Select Calendars EKCalendarChooser requires write only or full calendar access. In write only apps, the chooser behaves as writable calendars only and only allows a single writable calendar selection. Observing Changes Register for EKEventStoreChanged notifications to keep your UI in sync when events are modified outside your app (e.g., by the Calendar app or a sync). Always re fetch events after receiving this notification. Previously fetched EKEvent , EKReminder , and EKCalendar objects may be stale. The notification is posted on the main actor. Common Mistakes DON'T: Use legacy requestAccess(to:) on current systems Keep it only in the compatibility fallback from [Availability]( availability). DON'T: Save events to a read only calendar DON'T: Ignore timezone when creating events DON'T: Forget to commit batched saves DON'T: Mix EKObjects from different event stores Review Checklist [ ] Correct Info.plist usage description keys added for calendars and/or reminders [ ] Authorization follows the version split in [Availability]( availability) [ ] Write only calendar access used only for direct event creation, not event/calendar reads [ ] Authorization status checked before fetching or saving [ ] Full access required before any event or reminder fetch [ ] Single EKEventStore instance reused across the app [ ] Events saved to a writable calendar ( allowsContentModifications checked) [ ] Recurring event saves specify correct EKSpan ( .thisEvent vs .futureEvents ) [ ] Batched saves validate writable calendars, stage with commit: false , call throwing commit() , and on failure reset() unsaved state, discard every invalidated EKObject , then refetch or reconstruct before retry [ ] EKEventStoreChanged notification observed to refresh stale data [ ] Change observation uses the classic notification or guarded typed message per [Availability]( availability) [ ] Timezone set explicitly for location specific events [ ] EKObjects not shared across different event store instances [ ] EventKitUI delegates dismiss controllers in completion callbacks References Extended patterns (SwiftUI wrappers, predicate queries, batch operations): [references/eventkit patterns.md](references/eventkit patterns.md) [EventKit framework](https://sosumi.ai/documentation/eventkit) [EKEventStore](https://sosumi.ai/documentation/eventkit/ekeventstore) [EKEvent](https://sosumi.ai/documentation/eventkit/ekevent) [EKReminder](https://sosumi.ai/documentation/eventkit/ekreminder) [EKRecurrenceRule](https://sosumi.ai/documentation/eventkit/ekrecurrencerule) [EKCalendar](https://sosumi.ai/documentation/eventkit/ekcalendar) [EventKit UI](https://sosumi.ai/documentation/eventkitui) [EKEventEditViewController](https://sosumi.ai/documentation/eventkitui/ekeventeditviewcontroller) [EKCalendarChooser](https://sosumi.ai/documentation/eventkitui/ekcalendarchooser) [Accessing the event store](https://sosumi.ai/documentation/eventkit/accessing the event store) [Creating a recurring event](https://sosumi.ai/documentation/eventkit/creating a recurring event)