This study presents an investigation of oral narratives collected from heritage Egyptian and Palestinian Arabic speakers living in the United States. The focus is on a number of syntactic and morphological features in their production, such as word order, use of null subjects, selection of prepositions, agreement, and possession. The degree of codeswitching in their narratives was also investigated. The goal was to gain some insights into the Arabic linguistic competence of this group of speakers. The results show that although Arabic heritage speakers display significant competence in their heritage colloquial varieties, there are gaps in that knowledge. There also seems to be significant transfer from English, their dominant language.