Open the Find My app on another Apple device
Sign in to iCloud.com/find on a computer or phone
Select your iPhone from the Devices list
Check the last known location shown on the map
Turn on Notify When Found
Mark the iPhone as Lost
Add a phone number and message to the lock screen
Check Family Sharing devices if enabled
Review Google Maps Timeline if Location History was enabled
Check recent location data from your carrier account if available
Retrace your steps to the last known location
Contact places you recently visited
Call or text your number in case someone turns it on
Report the iPhone as lost to your carrier
File a police report if you believe it was stolen
Keep checking Find My for updates when it powers on
Remove the device from your account only if you are sure it cannot be recovered