(1) Background: Although numerous studies related to communication in a nursing context have been conducted, there is a lack of research considering the effects of personal and organisational communication factors on the self-efficacy for handoffs. This study aimed to identify the impact of communication competence and intra-organisational communication satisfaction on self-efficacy for handoffs among nurses. (2) Methods: This cross-sectional research was conducted between September and October 2018. In total, 203 registered nurses were invited to participate in the study by convenience sampling from five general hospitals in South Korea. Data were analysed using SPSS for t-test, one-way analysis of variance, Pearson’s correlation coefficients, and multiple regression analysis. (3) Results: In the final regression model, the adjusted R square was significant, explaining 24.2% of the variance in self-efficacy for handoffs (F = 22.43, p = 0.001) when the variable horizontal communication (β = 0.282, p < 0.001) was included in intra-organisational communication satisfaction. In addition, the longer the nurse’s experience in the current unit and the higher the communication competence, the more statistically significant the self-efficacy for handoffs was found to be (β = 0.215, p = 0.001 and β = 0.180, p = 0.008). (4) Conclusions: To enhance the self-efficacy for handoffs, nurse managers should foster an atmosphere that allows their staff nurses to interact freely and establish specific guidelines for handoffs through mutual communication.