How to show week numbers in the Calendar on an iPhone
2 min read · 4 steps · Updated 4 October 2026
Open Settings, tap Apps, then Calendar, and switch on Week Numbers. The Calendar then displays the week number next to every week of the year. The switch is off at first. The setting is in the Settings app, not in the Calendar app itself.
- Device
- iPhone
- Shown on
- iOS 26.5 (iPhone 17)
- App
- Settings
- Path
- Settings › Apps › Calendar
- Real screenshots
- 4 of 4 steps
- Checked
- October 2026
- Sources
- 1 official, linked below
Many workplaces plan by week number: delivery in week 42, holiday in week 31. The iPhone Calendar can show these numbers, but the switch is off when the phone is new and it is not inside the Calendar app.
The screenshots show iOS 26.5 on an iPhone 17. On older versions the rows have the same names, with a slightly different look.
Step by step
Open Settings and tap Apps
Apps is near the bottom of the main Settings list. On iOS 17 and earlier, Calendar is in the main list itself.
Tap Calendar
The apps are in alphabetical order, so Calendar is near the top, under C.
Switch on Week Numbers
It is in the group below Siri and Search. In the picture the switch is still off.
Look at the switch below it
Week View Starts On Today is the next row and is also off at first. Switched on, it shows the current day as the first day in Week view.
Good to know
Which day a week begins with is set on the same page: how to change the first day of the week in the iPhone Calendar.
To switch the numbers off again, go the same way and switch Week Numbers off.
In short: Settings, Apps, Calendar, Week Numbers on.
Links checked on 3 October 2026. Rules and prices change. Check the official source before you act.