It is generally expected that spatial planning integrates wildfire risk reduction considerations in areas affected by this hazard. However, many spatial planning systems are challenged to adequately deal with this risk. There is a need for applied understandings of planning systems characteristics that facilitate or impede wildfire risk reduction. Accordingly, this research explores spatial planning limitations to the integration of wildfire risk reduction measures by comparing spatial planning and wildfire risk reduction measures based on five key dimensions: structure, realm, spatial scale, territorial boundaries, and time scale. The research used a qualitative case study strategy of the Chilean spatial planning system, employing qualitative content analysis of key documents. The results show that the long-established characteristics of Chile's spatial planning limit its ability to accommodate wildfire risk reduction measures in the five dimensions analyzed. The research contributes to understanding some of spatial planning's constraints to manage wider complex challenges.