Professional development is used by teachers to improve their teaching to enhance student learning, and research indicates that the National Board Certification (NBC) process contains high-quality professional development characteristics. Engagement in the NBC process can lead to professional growth by changing teachers’ knowledge, instructional practices, and students’ learning. This quantitative study investigated the extent to which characteristics of the NBC process influenced National Board Certified Teachers’ (NBCTs) professional growth. Using an online survey, the study collected responses from 119 NBCTs who participated in a specific NBC support program. Key findings included that all 20 high-quality professional development characteristics investigated had a perceived positive influence on professional growth, with some notable differences. The characteristics involving individual analysis of student work and teaching videos along with reflection were perceived to be most important, while those centering on collaboration with other candidates were perceived as less important. Second, characteristics that had the greatest perceived impact were those that focused on changing pedagogy rather than increasing content knowledge. Furthermore, a significant relationship was found between the perceived importance of duration in the experience and the length of time the candidate was in the process: NBCTs who achieved in one year, as compared to NBCTs who achieved in two or three years, had statistically significant lower ratings on the influence that the duration had on their professional growth. Additionally, those who engaged in the process for financial reasons, as compared to professional growth, had a lower rating of perceived importance when all characteristics were combined.