How do I know the item was held by customs?

Hi,
I ship worldwide.
I would like to know, if the package didn't arrive to my buyers, how do i know it was hold by the their customs?
Will the customs let the buyer know by calling them or any kind of contact?
How do i know the package was lost in transit, or hold by customs?
It's been on my mind a while..

Thank you for explanation.
JEFF

Hi Jeff,

You can try and track your package through your shipper, most offer tracking feature.

More often than not customs will contact the owner of the package if their package is being held .

Hope this helps!