The aim of this study was to evaluate factors associated with rheumatologists' clinical work hours and patient volumes based on a national workforce survey in rheumatology. Adult rheumatologists who participated in a 2015 workforce survey were included (n = 255). Univariate analysis evaluated the relationship between demographics (sex, age, academic vs. community practice, billing fee for service vs. other plan, years in practice, retirement plans) and workload (total hours and number of ½-day clinics per week) or patient volumes (number of new and follow-up consults per week). Multiple linear regression models were used to evaluate the relationship between practice type, sex, age, and working hours or clinical volumes. Male rheumatologists had more ½-day clinics (p = 0.05) and saw more new patients per week (p = 0.001) compared with females. Community rheumatologists had more ½-day clinics and new and follow-up visits per week (all p < 0.01). Fee-for-service rheumatologists reported more ½-day clinics per week (p < 0.001) and follow-ups (p = 0.04). Workload did not vary by age, years in practice, or retirement plans. In multivariate analysis, community practice remained independently associated with higher patient volumes and more clinics per week. Female rheumatologists reported fewer clinics and fewer follow-up patients per week than males, but this did not affect the duration of working hours or new consultations. Age was not associated with work volumes or hours. Practice type and rheumatologist sex should be considered when evaluating rheumatologist workforce needs, as the proportion of female rheumatologists has increased over time and alternative billing practices have been introduced in many centers.