Large protected areas are often considered to be as important as population size in reducing extinction risk for large carnivores. However, the effectiveness of protected areas for large carnivore survival has rarely been tested where surrounding areas also provide suitable habitats. Using individual-based long-term data, we here show that three species of large carnivores all suffered higher risk of illegal killing inside three large national parks than in surrounding unprotected areas in northern Sweden. We suggest that this illegal killing is the result of low enforcement and public presence in these remote parks, which results in a low probability for poachers to be discovered. Our results demonstrate that size of protected areas alone may be a poor predictor of their conservation value for large carnivores. We warn against passive national park management, and advocate considering the ecological and socio-economic context present inside as well as outside protected areas. This article is protected by copyright. All rights reserved