Increasing costs of wildfire management have highlighted the need to better understand suppression expenditures and potential tradeoffs of land management activities that may affect fire risks. Spatially and temporally descriptive data is used to develop a model of wildfire suppression expenditures, providing new insights into the role of spatial and temporal heterogeneity in determining expenditures. Incorporating heterogeneity improves model fit and predictive ability over a model with data based on the point and time of fire ignition. The model is potentially useful for providing expenditure information for simulated fire applications and post-season evaluation of suppression activities.