This study investigates how different modes of a memorization activity in paired‐associate learning (PAL), namely pair work and individual work, can affect learners’ short‐ and long‐term retention of newly learned vocabulary items. In the aforementioned activity, two groups of Japanese college students studying English as a foreign language (EFL) learned 20 novel English vocabulary items using a second language–first language (L2–L1) list. First, the pair group worked in pairs; one member asked the other to state the L1 equivalent of the target items aloud for 2.5 min, and vice versa. Second, the members of the individual group memorized the L1 meanings of the target words for 5 minutes using their own methods. Subsequently, an immediate posttest and questionnaire survey regarding their preferred learning styles and strategies were conducted after the study session. Furthermore, a surprise delayed posttest was administered 3 weeks after the session. The results revealed that the individual group outperformed in the immediate posttest. However, the pair group scored significantly better in the delayed posttest. These results suggest that individual work is superior for memorizing a larger number of words in a short time but that memory can decay relatively quickly. Conversely, pair work may be superior for long‐term retention.