To examine the combined effects of maths anxiety (MA), maths self-efficacy (MSE), and maths interest (MI) on STEM career choice, we analysed self-report data from 7908 Twins Early Development Study participants, collected at ages 16 (MSE, MI), 18 (MA) and 21 (STEM career choice). When analysed in the same model, MSE did not independently predict STEM career choice. MI (OR = 1.75) was a stronger predictor than MA (OR = 0.79), which was not significant after controlling for maths achievement. MI was a significant positive predictor of STEM career choices for both males (OR = 1.88) and females (OR = 1.77). However, MA was only predictive for males (OR = 0.62), and MSE was only predictive for females in the unadjusted model (OR = 1.77). These results highlight the importance of nurturing maths interest to bridge the STEM skills gap, regardless of sex. Future research should consider the co-development of maths-related psychological constructs to further understand their influence on STEM career paths.