Background: The lack of a valid instrument to measure patient-centred care (PCC) in dietetic practice makes it challenging to evaluate how patient-centred dietitians are. The present study aimed to develop and psychometrically test a dietitian-reported inventory to measure PCC in dietetic practice. Methods: The inventory was compiled based on a literature review of existing validated scales that measured the dimensions of PCC. Next, the inventory was distributed as a cross-sectional survey to 180 Australian Accredited Practicing Dietitians who worked in primary care. Exploratory factor analysis was performed using principal factor analysis with Promax rotation. Cronbach's alpha (criteria ≥0.80), inter-item correlations and corrected item-total correlations (criteria 0.30–0.70) were computed to evaluate the internal consistency of each scale. Results: Five factors were extracted accounting for 56.9% of the variance. Most variables had strong loadings on only one factor. Factors were labelled as: shared decision-making; holistic and individualised care; patient–dietitian communication; knowing the patient; and caring patient–dietitian relationships. Cronbach's alpha was 0.94 for the total inventory and ranged from 0.73 to 0.91 for the individual factors. Inter-item correlations and corrected item-total correlations mostly fell in the desired range. Conclusions: The present study offers a preliminary, conceptually grounded dietitian-reported inventory, which is the first instrument developed and tested to measure PCC in dietetic practice. These findings illustrate the underlying factor structure of the inventory and support the reliability of the scales. With further testing, this inventory may provide useful to clinicians and researchers working to better understand and improve dietetic practice.