iCloud Alert Settings

  1. Go to Device Settings
  2. Select Calendar (or Mail, Contacts, Calendars in iOS9 and below)
  3. Scroll down to Default Alert Times
  4. Set Alerts to None

If this didn't help it's most probably an iCloud setting

  1. Login to
  2. Click on Settings at the left bottom and change Alerts option according to your preferences.


If the above didn't solve your problem, check the following alert settings:
Week Calendar >Settings > Calendar > New event defaults > Default alert
For older app versions see Settings > New Events & Templates > New Event Defaults > Default alert