Here’s where Apple’s new Silence Unknown Callers feature in iOS 13 comes in. Since the introduction of iOS 13 it’s been possible to set your phone so that it only receives calls from numbers in your Contacts or someone you have recently called.
You can set this up in Settings > Phone. Then Scroll to Silence Unknown Callers and make sure it’s switched on.
This is a great way to ensure you never receive another call from a window-sales person again. However, sometimes you might be the one who needs to get in touch with someone who doesn’t have your number. Perhaps you have a new number or perhaps you are borrowing a friend’s phone.
At least in this case you can leave a message for them, but in an emergency that may not be enough.
There is potentially a way around this: the number needs to be in their contacts, or it could be one of the Siri Suggestions. The best way to get a number into Siri Suggestions is to email them with your contact details. We can’t guarantee this will work if they don’t even open the email, but it might!
There are a few other reasons why your call might not get through, most obviously they may have turned their phone off, or they might have it on Do Not Disturb.
To rule out the phone being switched off you could ring from a different number, or disguise your number using the
relevant code for your country (141 from a UK landline, for instance), or by switching off call ID in the settings if you’re using an iPhone (Settings > Phone > Show My Caller ID, then switch it off). Of course if they have the iOS 13 Silence Unknown Callers feature you would need to call them from someone whose Contact information will definitely be in their iPhone.
If the phone really is switched off or set to divert, it will once again ring once and then go to voicemail. If they have Silence Unknown Callers on and the number you are calling from isn’t in their contacts you will also go to voicemail.
But if you were blocked, and the number you call from is in their contacts, either the person will pick up, or it will ring a few times until you ring off.
Note that this may well be regarded as a sneaky or even harassing thing to do. It might just be better to get the message passed on by the person whose phone you were planning to borrow.