Sanitation improvement is crucial in saving lives that are lost due to water contamination but progress towards achieving full sanitation coverage is still slow in low-income informal settlements in most developing countries. Furthermore, resources are being wasted on installing facilities that are later misused or never used because they do not meet the local demand. This study has used a mixed methods approach to identify how we can better stimulate demand for sanitation improvements in low-income informal settlements of the cities in sub-Saharan Africa. A comparative case study in three cities in East Africa (Kigali, Rwanda; Kampala, Uganda; and Kisumu, Kenya) involved a household stratified probability survey complemented with focus group discussions, interviews and deliberative forums. More than half of the respondents (59.7%) reported using sanitation facilities that are included in the JMP definition of improved sanitation. However, a high proportion of these facilities did not provide access to basic sanitation. A five progressive decision-stage sanitation demand model revealed that less than 12% of respondents indicated that they had considered installing a household sanitation facility with varied proportions at the different demand stages and between cities. Majority of those who were willingness to pay for sanitation improvements were at the no preference stage of demand and only a small proportion at the last stage of demand. The differences in sanitation coverage, barriers, motivations and level of demand for sanitation improvements within and between cities relate to the geophysical and socio-economic characteristics of the settlements/cities and highlight the need to tailor programmes to meet the local demand for sanitation improvements, specific for each community. Appropriate interventions should be identified for the category of households at each stage of demand through engagement of key stakeholders to facilitate their demand progression to actualization. Stimulating demand for sanitation improvements will enhance acceptability and usage of the facility to result in increased access and minimize waste of resources.