Unlike Lexical Projections, Functional Projections (Extended Projections) are more of an ‘abstract’ in nature. Therefore, Functional Projections seem to be acquired later than Lexical Projections by the L2 learners. The present study investigates Iranian L2 learners’ acquisition of English Extended Projections taking into account their level of grammatical proficiency. Specifically, the aim is to identify the level of grammatical proficiency at which the acquisition of Extended Projections could occur in the process of learning English by the Iranian students. Two hundred and seventy Iranian female L2 learners of English participated in this study. Participants were administered three tests with a ten-day interval between each test. First, an Oxford Placement Test (OPT) was used to classify the participants’ level of grammatical proficiency. Second, a Grammaticality Judgment Task (GJT) was administered in order to assess the learners’ ability to recognize grammatical problems in Extended Projections. Finally, a picture description task (PDT) was administered to examine the learners’ ability to produce grammatical Extended Projections. The results indicated that the learners are able to recognize and produce English Extended Projections even at lower levels of grammatical proficiency. The results also showed that the learner’s recognition and production of English Extended Projection improves with their increased level of grammatical proficiency. Manuscript profile