I’ve found an iPhone on Sky contract. How can I tell the owner?

[Mecca]

I need to contact the owner of a phone I've found. It's locked. Any suggestions? 

[caesarome]

Put the details out on social media perhaps as there will not be anyway you can get into a locked iphone.

[Daniel0210]

@Mecca 

Hand it in to the police as found property. Although you're trying to help, it's not your responsibility to find the loser.

[TimmyBGood]

@Mecca 

Sky would be absolutely forbidden from giving you any information, and couldn't themselves access the device to identify its user if it doesn't have an external serial number.  Apple themselves refuse to bypass user security even when law enforcement is involved.

[twilight+princess]

Supposedly by activating Siri then asking who owns this phone it would bring up the owner's details which could contain other contact details for them or allow you call someone on their friends list.
If it shows a name then you could try social media.
Otherwise hand it to the Police.