Question

If two organisms are in the same phylum what other classification do they share

Answer 1

If two organisms are in the same Phylum they are also in the same Kingdom and Domain.  

The domain is the higher level of classification and it consists of three groups: Archaea, Bacteria, and Eukarya. Kingdom is the second highest level of classification and most often is divided into Animalia, Plantae, Fungi, Protista, Archaea/Archaeabacteria, and Bacteria/Eubacteria.
Below the phylum, there are a class, order, family, genus and species.