Criterion validity of a novel accelerometry device that measures caloric expenditure (Fitbit) was evaluated against a self-report estimation of caloric expenditure (Community Healthy Activities Model Program for Seniors) in older adults. Community Health Activities Model Program for Seniors and Fitbit estimates of total caloric expenditure per day were significantly correlated (r = .61, p < .05). Bland–Altman plots indicated that 70 percent of participants’ data were within 1 standard deviation of the mean difference between measures. These preliminary findings suggest that the Fitbit may be considered a viable instrument for measuring daily caloric expenditure among older adults. However, further work is required to determine the optimal measurement technique for caloric expenditure among older adults.