The immediate impact of and reaction to demonetisation are documented and examined through a survey of around 200 families living in 28 slum or lower-income neighbourhoods in Mumbai in early December 2016. A drop in family income is recorded with wide variation across different groups and occupation types. There is also a drop in consumption as well as changes in the families’ savings in November. Finally, we find that the majority of respondents view the policy overall as positive, including the majority of those who experienced some loss of income in November.