Morbidity and its treatment can be potentially burdensome or even catastrophic for poor households. While public policy has shown some response to this phenomenon, there is scope for improvement of the coverage of the programmes. Health insurance schemes like the Rashtriya Swasthya Bima Yojana cover only conditional hospitalisation expenses. This paper argues that treatment cost incurred on ailments not requiring hospitalisation is also a substantial burden on the urban poor. Based on a case study of 150 slum households in south Delhi with a history of treated ailments within a specific recall period, the study estimates the degree and distribution of this burden across socio-economic and disease characteristics in the sample. The paper argues for a more holistic approach in social safety nets like the RSBY, and for explicitly including uncovered healthcare payments in measurement of the poverty lines for a more accurate estimation of the marginalised.