Background: Critical thinking (CT) is an essential cognitive skill for nurses, particularly in high-stakes environments such as surgical wards. Although previous studies have examined the relationship between CT and clinical outcomes, few have investigated how CT develops across different nursing experience levels, especially within the Indian healthcare context.

Aim: To assess and explain the progression of critical thinking skills and dispositions among nurses at different stages of clinical experience in surgical units.

Methods: A sequential explanatory mixed-methods design was used. In the quantitative phase, 40 nurses were stratified by experience level (novice, competent, expert) and assessed using adapted versions of the California Critical Thinking Skills Test (CCTST) and Disposition Inventory (CCTDI). Data were analyzed using descriptive statistics, ANOVA, and post hoc tests. In the qualitative phase, 20 nurses were selected for in-depth semi-structured interviews, analyzed thematically. A joint display matrix was used for data integration.

Results: ANOVA revealed significant differences in CCTST (F (2,37) = 5.94, p = 0.005) and CCTDI (F (2,37) = 4.77, p = 0.012) scores across experience levels. Experts outperformed novices with medium-to-large effect sizes. Thematic analysis yielded three key themes: (1) evolution of decision-making autonomy, (2) depth of reflective practice, and (3) mentorship as a developmental catalyst. Integrated analysis confirmed convergence between score trends and narrative insights.

Conclusion: Critical thinking among nurses matures with experience, reflecting both cognitive growth and attitudinal development. Mentorship and structured reflection appear critical to this progression. Findings support experience-sensitive CT training and inform workforce development strategies in surgical care environments.