This scrip (not a typo, a scrip is an RT Script) can be added in the global scrip section and will automatically put a ticket in the proper queue based on the sender's e-mail address. In this case, we have senders coming from different domains (@example.net and @example2.com), and we want to put them into the queue's Example and Example 2 Queue when a new ticket arrives. Note: the queues must exist before this.

The hash %domain_map contains a Regular Expression (aka regex) to match. If the regex matches, the new ticket will be placed in the proper queue.

Note: A handy regex tester I use quite a bit is located at https://regex101.com/

# Written by RWR, taken from
# https://forum.bestpractical.com/t/changing-queue-based-on-incoming-email-address/20925
 
# hash of all the possible domains, and matching queues
 
my %domain_map = (
   '@.?example.net' => 'Example',
   '@.?example2.com' => 'Example 2 Queue'
);
 
#Check each of our defined domains for a match
foreach my $domainKey (keys %domain_map ) {
   if ( $self->TicketObj->RequestorAddresses =~ /^.*?${domainKey}/ ) {
      # Domain matches - move to the right queue
      $self->TicketObj->SetQueue($domain_map{$domainKey});
   }
}
return 1;