The typical dial pattern to turn off caller-id for a single call is *67, but
the T-Mo support DOC-4041 about "short codes" suggests that it
is #31# instead, and *31# as the inverse to "un-hide" like *82. Is this
carrier-dependent, i.e. the network will handle the dialed string the
same way regardless of originating device type?
I've been using *67 on calls where I care, and got the rude shock recently
that it was *not* working, and my number was being passed on anyway.
Regardless of custom nonstandard prefixes that some T-mo engineer
might have thought was a cute idea, why not make *67 also equivalent,
since the intent of someone dialing that is quite clear??
[I assume this is the right sub-forum for a question like this..]
I'm going to be honest with you -- I don't think this has ever crossed my mind as being different from other carriers. I know that *67 works with most numbers but not all of them. To answer your first question, I don't know if this is carrier dependent as it has been over a decade since I've had a different carrier. I will most definitely pass your feedback about *67 along to our engineering team.
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