Lost iphone

Sorry, there is no option to locate it by using the serial number.

Also see the following from If Find My iPhone or Find My iPad isn't enabled on your missing device - Apple Support

If your missing device doesn't appear in the Find My app or at iCloud.com/find, you didn't turn on Find My. There's no other Apple service that can find, track, or flag your device for you. But there are steps that you can take to help protect your data.

Or if you did have it setup with Find My turned on, see: If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

Click here for information; in addition, post notices around where you lost it, and if applicable, contact the Lost & Found department of the facility where you lost it.

The serial number can only be used to check if an already-found iPhone is yours.

(218083)