OBJECTIVE Practice-based information may allow policy makers and associations the opportunity to interpret utilization rates and anticipate the impact of future growth of professions. The objective of this study was to assess the association between income and specific personal, practice, and treatment characteristics in a sample of Ontario chiropractors. METHODS Descriptive and regression analyses were used to assess end-of-year practice summary data obtained from a professional billing software program voluntarily submitted by 731 individual chiropractors. RESULTS The model explained 65% of the variance in income. Significant explanatory factors regarding income were those related to treatment characteristics, with the largest contribution made by the total number of new patients seen in the year, which uniquely contributed 17% of the total variance. Personal and practice-related characteristics made significant but relatively small contributions; however, the location of the practice and years since graduation appear to impact income, especially in the formative years of practice development. CONCLUSION The variance in annual practitioner income was predicted by a combination of personal, practice, and treatment characteristics but not surprisingly primarily by the total number of new patients seen in the year. A negative association between average treatment costs and number of patients seen suggests cost sensitivity. The results provide important benchmarks that can be used to guide expectations of new graduates and to assess future trends. Further work is needed to determine if the findings can be generalized.