It is obviously two different language varieties: it varies among countries: there is registered mail, certified mail, and delivery-recorded mail , for instance.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
petusekFrom what Google seems to have found, postal receipt appears to pop up predominantly on servers based in the U.S.A. whereas certificate of posting can be seen mostly on British-based web pages (that answers you question - no, I don't).So, is this just an illusion or misinterpretation of what I've seen?That seems a reasonable conclusion.